Diketopyrrolopyrrole polymers for use in organic semiconductor devices

ABSTRACT

The present invention relates to polymers comprising one or more (repeating) unit(s) of the formula (I) which are characterized in that Ar 1  and Ar 1′  are independently of each other are an annulated (aromatic) heterocyclic ring system, containing at least one thiophene ring, which may be optionally substituted by one, or more groups, and their use as organic semiconductor in organic devices, especially in organic photovoltaics (solar cells) and photodiodes, or in a device containing a diode and/or an organic field effect transistor. The polymers according to the invention have excellent solubility in organic solvents and excellent film-forming properties. In addition, high efficiency of energy conversion, excellent field-effect mobility, good on/off current ratios and/or excellent stability can be observed, when the polymers according to the invention are used in organic field effect transistors, organic photovoltaics (solar cells) and photodiodes.

The present invention relates to polymers comprising one or more(repeating) unit(s) of the formula I, and their use as organicsemiconductor in organic devices, especially in organic photovoltaics(solar cells) and photodiodes, or in a device containing a diode and/oran organic field effect transistor. The polymers according to theinvention have excellent solubility in organic solvents and excellentfilm-forming properties. In addition, high efficiency of energyconversion, excellent field-effect mobility, good on/off current ratiosand/or excellent stability can be observed, when the polymers accordingto the invention are used in organic field effect transistors, organicphotovoltaics (solar cells) and photodiodes.

U.S. Pat. No. 6,451,459 (cf. B. Tieke et al., Synth. Met. 130 (2002)115-119; Macromol. Rapid Commun. 21 (4) (2000) 182-189) describesdiketopyrrolopyrrole based polymers and copolymers comprising thefollowing units

wherein x is chosen in the range of from 0.005 to 1, preferably from0.01 to 1, and y from 0.995 to 0, preferably 0.99 to 0, and whereinx+y=1, and wherein Ar¹ and Ar² independently from each other stand for

and m, n being numbers from 1 to 10, andR¹ and R² independently from each other stand for H, —C(O)O—C₁-C₁₈alkyl,perfluoro-C₁-C₁₂alkyl, unsubstituted C₆-C₁₂aryl or one to three timeswith C₁-C₁₂alkyl, C₁-C₁₂alkoxy, or halogen substituted C₆-C₁₂aryl,C₁-C₁₂alkyl-C₆-C₁₂aryl, or C₆-C₁₂aryl-C₁-C₁₂alkyl, R³ and R⁴ preferablystand for hydrogen, C₁-C₁₂alkyl, C₁-C₁₂alkoxy, unsubstituted C₆-C₁₂arylor one to three times with C₁-C₁₂alkyl, C₁-C₁₂alkoxy, or halogensubstituted C₆-C₁₂aryl or perfluoro-C₁-C₁₂alkyl, andR⁵ preferably stands for C₁-C₁₂alkyl, C₁-C₁₂alkoxy, unsubstitutedC₆-C₁₂aryl or one to three times with C₁-C₁₂alkyl, C₁-C₁₂alkoxy, orhalogen substituted C₆-C₁₂aryl, or perfluoro-C₁-C₁₂alkyl, and their usein EL devices. The following polymer

is explicitly disclosed in Tieke et al., Synth. Met. 130 (2002) 115-119.The following polymers

are explicitly disclosed in Macromol. Rapid Commun. 21 (4) (2000)182-189.

WO05/049695 discloses diketopyrrolopyrrole (DPP) based polymers andtheir use in PLEDs, organic integrated circuits (O—ICs), organic fieldeffect transistors (OFETs), organic thin film transistors (OTFTs),organic solar cells (O—SCs), or organic laser diodes, but fails todisclose the specific DPP based polymers of formula I.

A preferred polymer comprises a repeating unit of formula

and a repeating unit

Ar³

, whereinR¹ and R² are independently of each other a C₁-C₂₅alkyl group,especially a C₄-C₁₂alkyl group, which can be interrupted by one or moreoxygen atoms, and Ar¹ and Ar² are independently of each other a group offormula

wherein —Ar³— is a group of formula

whereinR⁶ is hydrogen, C₁-C₁₈alkyl, or C₁-C₁₈alkoxy, and R³² is methyl, Cl, orOMe, and R⁸ is H, C₁-C₁₈alkyl, or C₁-C₁₈alkyl which is substituted by Eand/or interrupted by D, especially C₁-C₁₈alkyl which is interrupted by—O—.

In Example 12 the preparation of the following polymer is described:

WO08/000,664 describes polymers comprising (repeating) unit(s) of theformula

Ar¹ and Ar^(1′) are preferably the same and are a group of formula

especially

andAr², Ar^(2′), Ar³, Ar^(3′), Ar⁴ and Ar^(4′) are independently of eachother a group of formula

whereinp stands for 0, 1, or 2, R³ may be the same or different within onegroup and is selected from C₁-C₂₅alkyl, which may optionally besubstituted by E and/or interrupted by D, or C₁-C₁₈alkoxy, which mayoptionally be substituted by E and/or interrupted by D;R⁴ is C₆-C₂₅alkyl, which may optionally be substituted by E and/orinterrupted by D, C₆-C₁₂aryl, such as phenyl, naphthyl, or biphenylyl,which may optionally be substituted by G, C₁-C₂₅alkoxy, which mayoptionally be substituted by E and/or interrupted by D, orC₇-C₁₅aralkyl, wherein ar may optionally be substituted by G,D is —CO—, —COO—, —S—, —SO—, —SO₂—, —O—, —NR²⁵—, wherein R²⁵ isC₁-C₁₂alkyl, such as methyl, ethyl, n-propyl, iso-propyl, n-butyl,isobutyl, or sec-butyl;E is —OR²⁹; —SR²⁹; —NR²⁵R²⁵; —COR²⁸; —COOR²⁷; —CONR²⁵R²⁵; or —CN;wherein R²⁵, R²⁷, R²⁸ and R²⁹ are independently of each otherC₁-C₁₂alkyl, such as methyl, ethyl, n-propyl, iso-propyl, n-butyl,isobutyl, sec-butyl, hexyl, octyl, or 2-ethyl-hexyl, or C₆-C₁₄ aryl,such as phenyl, naphthyl, or biphenylyl,G has the same preferences as E, or is C₁-C₁₈alkyl, especiallyC₁-C₁₂alkyl, such as methyl, ethyl, n-propyl, iso-propyl, n-butyl,isobutyl, sec-butyl, hexyl, octyl, or 2-ethyl-hexyl.

PCT/EP2009/063767 discloses polymers comprising one or more (repeating)unit(s) of the formula

whereinAr¹, Ar^(1′), Ar³ and Ar^(3′) are independently of each other a group offormula

and their use as organic semiconductor in organic devices.

PCT/EP2009/063769 relates to polymers comprising one or more (repeating)unit(s) of the formula

A-D

, and at least one (repeating) unit(s) which is selected from repeatingunits of the formula

B-D

,

A-E

, and

B-E

,

a polymer comprising one or more (repeating) unit(s) of the formula

ora polymer comprising one or more (repeating) unit(s) of the formula

wherein A is a group of formula

Ar²¹, Ar^(21′), Ar³¹, Ar^(31′), Ar¹ and Ar^(1′) are independently ofeach other a group of formula

Ar², and Ar^(2′) are independently of each other a group of formula

B, D and E are independently of each other a group of formula

or formula

Ar⁸ and Ar^(8′) are independently of each other a group of formula

JP2007266285 relates to a field effect transistor comprising a compoundrepresented by a formula

as a semiconductor material, wherein X¹ and X² each independently denotean oxygen atom, a sulfur atom, or a selenium atom, and R₁; R₂, R₃ and R₄each independently denote a hydrogen atom, a substitutable aliphatichydrocarbon group, or a substitutable aromatic group. The following DPPcompound is explicitly disclosed:

EP2034537A2 is directed to a thin film transistor device comprising asemiconductor layer, the semiconductor layer comprising a compoundcomprising a chemical structure represented by:

wherein each X is independently selected from S, Se, O, and NR″, each R″is independently selected from hydrogen, an optionally substitutedhydrocarbon, and a hetero-containing group, each Z is independently oneof an optionally substituted hydrocarbon, a hetero-containing group, anda halogen, d is a number which is at least 1, e is a number from zero to2; a represents a number that is at least 1; b represents a number from0 to 20; and n represents a number that is at least 1.

Among others the following polymers are explicitly disclosed:

wherein n is the number of repeat units and can be from about 2 to about5000, R′″ and R″″ can be the same or different substituent, and whereinthe substituent is independently selected from the group consisting ofan optionally substituted hydrocarbon group and a heteroatom-containinggroup.

EP2075274A1, which enjoys an earlier priority date (27 Dec. 2007) thanthe present invention (5 Dec. 2008), but has been published (1 Jan.2009) after the priority date of the present invention, discloses asoluble polythiophene derivative containing highly coplanar repeatingunits. The coplanar characteristic of the TPT(thiophene-phenylene-thiophene) units improves the degree ofintramolecular conjugation and intermolecular π-π interaction.

The production of the following polymer by Stille CouplingPolymerisation is described in Example 12 of EP2075274A1:

(molecular weight: 28589 g/mol).

It is the object of the present invention to provide polymers, whichshow high efficiency of energy conversion, excellent field-effectmobility, good on/off current ratios and/or excellent stability, whenused in organic field effect transistors, organic photovoltaics (solarcells) and photodiodes.

Said object has been solved by polymers comprising one or more(repeating) unit(s) of the formula

wherein a is 1, 2, or 3, a′ is 0, 1, 2, or 3; b is 0, 1, 2, or 3; b′ is0, 1, 2, or 3; c is 0, 1, 2, or 3; c′ is 0, 1, 2, or 3; d is 0, 1, 2, or3; d′ is 0, 1, 2, or 3; with the proviso that b′ is not 0, if a′ is 0;R¹ and R² may be the same or different and are selected from hydrogen, aC₁-C₁₀₀alkyl group, —COOR¹⁰², a C₁-C₁₀₀alkyl group which is substitutedby one or more halogen atoms, hydroxyl groups, nitro groups, —CN, orC₆-C₁₈aryl groups and/or interrupted by —O—, —COO—, —OCO—, or —S—; aC₇-C₁₀₀arylalkyl group, which can be substituted one to three times withC₁-C₈alkyl and/or C₁-C₈alkoxy; a carbamoyl group, C₅-C₁₂cycloalkyl,which can be substituted one to three times with C₁-C₈alkyl and/orC₁-C₈alkoxy; a C₆-C₂₄aryl group, in particular phenyl or 1- or2-naphthyl, which can be substituted one to three times with C₁-C₈alkyl,C₁-C₈thioalkoxy, and/or C₁-C₈alkoxy, or pentafluorophenyl,Ar¹ and Ar^(1′) are independently of each other are an annulated(aromatic) heterocyclic ring system, containing at least one thiophenering, which may be optionally substituted by one, or more groups,Ar², Ar^(2′), Ar³, Ar^(3′), Ar⁴ and Ar^(4′) have the meaning of Ar¹, orare independently of each other

whereinone of X³ and X⁴ is N and the other is CR⁹⁹,R⁹⁹, R¹⁰⁴ and R^(104′) are independently of each other hydrogen,halogen, especially F, or a C₁-C₂₅alkyl group, especially a C₄-C₂₅alkyl,which may optionally be interrupted by one or more oxygen or sulphuratoms, a C₇-C₂₅aralkyl group, or a C₁-C₂₅alkoxy group,R¹⁰⁵, R^(105′), R¹⁰⁶ and R^(106′) are independently of each otherhydrogen, halogen, C₁-C₂₅alkyl, which may optionally be interrupted byone or more oxygen or sulphur atoms, C₇-C₂₅aralkyl, or C₁-C₁₈alkoxy,R¹⁰⁷ is C₇-C₂₅aralkyl, C₆-C₁₈aryl; C₆-C₁₈aryl which is substituted byC₁-C₁₈alkyl, C₁-C₁₈perfluoroalkyl, or C₁-C₁₈alkoxy; C₁-C₁₈alkyl;C₁-C₁₈alkyl which is interrupted by —O—, or —S—; or —COOR¹⁰³; R¹⁰³ isC₁-C₅₀alkyl, especially C₄-C₂₅alkyl;R¹⁰⁸ and R¹⁰⁹ are independently of each other H, C₁-C₂₅alkyl,C₁-C₂₅alkyl which is substituted by E and/or interrupted by D,C₇-C₂₅aralkyl, C₆-C₂₄aryl, C₆-C₂₄aryl which is substituted by G,C₂-C₂₀heteroaryl, C₂-C₂₀heteroaryl which is substituted by G,C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₁-C₁₈alkoxy, C₁-C₁₈alkoxy which issubstituted by E and/or interrupted by D, or C₇-C₂₅aralkyl, or R¹⁰⁸ andR¹⁰⁹ together form a group of formula whereinR¹¹⁰ and R¹¹¹ are independently of each other H, C₁-C₁₈alkyl which issubstituted by E and/or interrupted by D, C₆-C₂₄aryl, C₆-C₂₄aryl whichis substituted by G, or C₂-C₂₀heteroaryl, or C₂-C₂₀heteroaryl which issubstituted by G, orR¹⁰⁸ and R¹⁰⁹ together form a five or six membered ring, whichoptionally can be substituted by C₁-C₁₈alkyl, C₁-C₁₈alkyl which issubstituted by E and/or interrupted by D, C₆-C₂₄aryl, C₆-C₂₄aryl whichis substituted by G, C₂-C₂₀heteroaryl, C₂-C₂₀heteroaryl which issubstituted by G, C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₁-C₁₈alkoxy,C₁-C₁₈alkoxy which is substituted by E and/or interrupted by D, orC₇-C₂₅aralkyl,D is —CO—, —COO—, —S—, —O—, or NR¹¹²—,E is C₁-C₈thioalkoxy, C₁-C₈alkoxy, CN, —NR¹¹²R¹¹³, —CONR¹¹²R¹¹³, orhalogen,G is E, or C₁-C₁₈alkyl, andR¹¹² and R¹¹³ are independently of each other H; C₆-C₁₈aryl; C₆-C₁₈arylwhich is substituted by C₁-C₁₈alkyl, or C₁-C₁₈alkoxy; C₁-C₁₈alkyl; orC₁-C₁₈alkyl which is interrupted by —O—.

Most preferably R¹⁰⁴, R^(104′), R¹⁰⁵, R^(105′), R¹⁰⁶, R^(106′), R¹⁰⁷,R¹⁰⁸, R¹⁰⁹ are independently of each other hydrogen, or C₁-C₂₄alkyl.

Advantageously, the polymer of the present invention, or an organicsemiconductor material, layer or component, comprising the polymer ofthe present invention can be used in organic photovoltaics (solar cells)and photodiodes, or in an organic field effect transistor (OFET).

The term polymer comprises oligomers as well as polymers. The oligomersof this invention have a weight average molecular weight of <4,000Daltons. The polymers of this invention preferably have a weight averagemolecular weight of 4,000 Daltons or greater, especially 4,000 to2,000,000 Daltons, more preferably 10,000 to 1,000,000 and mostpreferably 10,000 to 100,000 Daltons. Molecular weights are determinedaccording to high-temperature gel permeation chromatography (HT-GPC)using polystyrene standards. The polymers of this invention preferablyhave a polydispersity of 1.01 to 10, more preferably 1.1 to 3.0, mostpreferred 1.5 to 2.5.

An annulated (aromatic) heterocyclic ring system, containing at leastone thiophene ring, means an annulated hetero-2-, -3-, -4-, -5-, -6-etc. ring system, which comprises at least one thiophene ring and whichmay be optionally substituted by one, or more groups. That is, the term“annulated” means that the hetero ring system consists of a thiophenering and at least one further aromatic, or heteroaromatic ring. Thediscrete rings can be aromatic, or heteroaromatic. The hetero ringsystem contains preferably 1, 2, 3, or 4 thiophene rings. In a preferredembodiment of the present invention the hetero ring system comprises atleast two thiophene rings. In another preferred embodiment of thepresent invention the bonding to the DPP skeleton and another repeatingunit is effected via two different rings of the annulated (aromatic)heterocyclic ring system.

Examples of annulated (aromatic) heterocyclic ring systems are thegroups of formula Xa to Xz and XIa to XIm mentioned below:

whereinR³ and R^(3′) are independently of each other hydrogen, halogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one or more oxygen or sulphur atoms, C₇-C₂₅aralkyl, or C₁-C₂₅alkoxy;R⁴, R^(4′), R⁵, R^(5′), R⁶ and R^(6′) are independently of each otherhydrogen, halogen, C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which mayoptionally be interrupted by one or more oxygen or sulphur atoms,C₇-C₂₅aralkyl, or C₁-C₂₅alkoxy;R¹¹⁴ is C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally beinterrupted by one, or more oxygen, or sulphur atoms,R⁷, R^(7′), R⁹ and R^(9′) are independently of each other hydrogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one, or more oxygen, or sulphur atoms, or C₇-C₂₅aralkyl,R⁸ and R^(8′) are independently of each other hydrogen, C₇-C₂₅aralkyl,C₆-C₁₈aryl; C₆-C₁₈aryl which is substituted by C₁-C₁₈alkyl, orC₁-C₁₈alkoxy; or C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which mayoptionally be interrupted by one or more oxygen or sulphur atoms;R¹¹ and R^(11′) are independently of each other C₁-C₂₅alkyl group,especially a C₁-C₈alkyl group, or a phenyl group, which can besubstituted one to three times with C₁-C₈alkyl and/or C₁-C₈alkoxy;R¹² and R^(12′) are independently of each other hydrogen, halogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one, or more oxygen, or sulphur atoms, C₇-C₂₅aralkyl, C₁-C₂₅alkoxy,or

R¹³, wherein R¹³ is a C₁-C₁₀alkyl group, or a tri(C₁-C₈alkyl)silylgroup.

In a preferred embodiment of the present invention the annulated(aromatic) heterocyclic ring system is selected from groups of formulaXa, Xb, Xc, Xd, and Xg. In another preferred embodiment of the presentinvention the annulated (aromatic) heterocyclic ring system is selectedfrom groups of formula Xe, Xf, Xh, Xi, Xj, Xk, Xm, Xn, Xq, Xr, Xv, Xx,Xy, XIa, XIb, XIg, XIh, Xii and XIl.

R¹ and R² can be different, but are preferably the same. Preferably, R¹and R² independently from each other stand for C₁-C₁₀₀alkyl,C₅-C₁₂cycloalkyl, which can be substituted one to three times withC₁-C₈alkyl and/or C₁-C₈alkoxy, phenyl or 1- or 2-naphthyl which can besubstituted one to three times with C₁-C₈alkyl and/or C₁-C₈alkoxy, or—CR¹⁰¹R¹⁰²—(CH₂)_(m)-A³, wherein R¹⁰¹ and R¹⁰² stand for hydrogen, orC₁-C₄alkyl, A³ stands for phenyl or 1- or 2-naphthyl, which can besubstituted one to three times with C₁-C₈alkyl and/or C₁-C₈alkoxy, and mstands for 0 or 1. R¹ and R² are more preferably a C₈-C₃₆ alkyl group,especially a C₁₂-C₂₄alkyl group, such as n-dodecyl, tridecyl,tetradecyl, pentadecyl, hexadecyl, 2-ethyl-hexyl, 2-butyl-hexyl,2-butyl-octyl, 2-hexyldecyl, 2-decyl-tetradecyl, heptadecyl, octadecyl,eicosyl, heneicosyl, docosyl, or tetracosyl. In a particularly preferredembodiment of the present invention R¹ and R² are a 2-hexyldecyl, or2-decyl-tetradecyl group.

Advantageously, the groups R¹ and R² can be represented by formula

wherein m1=n1+2 and m1+n1≦24. Chiral side chains, such as R¹ and R², caneither be homochiral, or racemic, which can influence the morphology ofthe polymers.

Preferably a is 1, a′ is 1; b is 0, or 1; b′ is 0, or 1; c is 0, or 1;c′ is 0, or 1; d is 0, 1, 2, or 3; d′ is 0, 1, 2, or 3. If a′ is 0, b′is not 0. Examples of groups wherein d, or d′ are 2, or 3 are shownbelow:

If a substituent, such as, for example R¹⁰⁴ and R^(104′), occurs morethan one time in a group, it can be different in each occurrence.

As indicated by the formula

the group

can be arranged in the polymer chain in two ways

The notation

should comprise both possibilities. The same applies for other groups,which can be arranged in different ways in the monomer and/or polymers.

The groups

Ar⁴

_(d)

Ar³

_(c)

Ar²

_(b)

Ar¹

_(a) and

Ar^(1′)

_(a′)

Ar^(2′)

_(b′)

Ar^(3′)

_(c′)

Ar^(4′)

_(d′) can be different, but are preferably the same. In the preferredcompounds Ia to Iv mentioned below the groups

Ar⁴

_(d)

Ar³

_(c)

Ar²

_(b)

Ar¹

_(a) and

Ar^(1′)

_(a′)

Ar^(2′)

_(b′)

Ar^(3′)

_(c′)

Ar^(4′)

_(d′) are the same. In principal, said groups may be different, which incase of compound Ia may result in compound

which according to the present invention is less preferred.

In a preferred embodiment of the present invention the polymer comprisesone or more (repeating) unit(s) of the formula

whereinR¹ is a C₈-C₃₆alkyl group,R³ is hydrogen, halogen, C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which mayoptionally be interrupted by one or more oxygen or sulphur atoms,C₇-C₂₅aralkyl, or C₁-C₂₅alkoxy;R⁴, R^(4′), R⁵, R^(5′) and R⁶ are independently of each other hydrogen,halogen, C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally beinterrupted by one or more oxygen or sulphur atoms, C₇-C₂₅aralkyl, orC₁-C₂₅alkoxy;R⁷, R^(7′), R⁹ and R^(9′) are independently of each other hydrogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one, or more oxygen, or sulphur atoms; or C₇-C₂₅aralkyl,R⁸ is C₇-C₂₅aralkyl, C₆-C₁₈aryl; C₆-C₁₈aryl which is substituted byC₁-C₁₈alkyl, or C₁-C₁₈alkoxy;or C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally beinterrupted by one or more oxygen or sulphur atoms, andR¹² and R^(12′) are independently of each other hydrogen, halogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one, or more oxygen, or sulphur atoms, C₁-C₂₅alkoxy, or

R¹³, wherein R¹³ is a C₁-C₁₀alkyl group, or a tri(C₁-C₈alkyl)silylgroup.

Most preferred

R¹ is C₈-C₃₆alkyl,

R³ is hydrogen or C₁-C₂₅alkyl;

R⁴, R^(4′), R⁵, R^(5′) and R⁶ are independently of each other hydrogenor C₁-C₂₅alkyl;

R⁷, R^(7′), R⁹ and R^(9′) are independently of each other hydrogen orC₁-C₂₅alkyl;

R⁸ is C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, and

R¹² and R^(12′) are independently of each other hydrogen, halogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one, or more oxygen, or sulphur atoms, C₁-C₂₅alkoxy, or

R¹³, wherein R¹³ is a C₁-C₁₀alkyl group, or a tri(C₁-C₈alkyl)silylgroup.

In said embodiment of the present invention compounds of the formulasIa, Ic, Id, If, Ih, Ik, Il, In, Io, Iq, Ir, It, or Iu are mostpreferred, wherein

R¹ is C₈-C₃₆alkyl,

R³ is hydrogen, halogen or C₁-C₂₅alkyl;

R⁴, R^(4′), R⁵, R^(5′) and R⁶ are independently of each other hydrogen,halogen, or C₁-C₂₅alkyl;

R⁷, R^(7′), R⁹ and R^(9′) are independently of each other hydrogen, orC₁-C₂₅alkyl;

R⁸ is C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, and

R¹² and R^(12′) are independently of each other hydrogen, halogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one, or more oxygen, or sulphur atoms, C₁-C₂₅alkoxy, or

R¹³, wherein R¹³ is a C₁-C₁₀alkyl group, or a tri(C₁-C₈alkyl)silylgroup.

In a preferred embodiment of the present invention the polymer is ahomopolymer of formula *

A

_(n)*, wherein A is as defined above; n is number which results in amolecular weight of 4,000 to 2,000,000 Daltons, more preferably 10,000to 1,000,000 and most preferably 10,000 to 100,000 Daltons. n is usuallyin the range of 4 to 1000, especially 4 to 200, very especially 5 to150.

In said embodiment A is preferably a repeating unit of formula (Ia),(Ib), (Ic), (Id), (Ie), (If), (Ig), (Ih), (Ii), (Ij), (Ik), (Il), (Im),(In), (Io), (Ip), (Iq), (Ir), (Is), (It), or (Iu) as defined above.

In a further preferred embodiment of the present invention the polymercomprises one or more (repeating) unit(s) of the formula *

A

* and *

COM¹

* (II), wherein

A is a repeating unit of formula (I), and

—COM¹- is a repeating unit, which is selected from a group of formulaAr¹, such as, for example,

whereinone of X⁵ and X⁶ is N and the other is CR¹⁴,R¹⁴, R^(14′), R¹⁷ and R^(17′) are independently of each other hydrogen,halogen, C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally beinterrupted by one or more oxygen or sulphur atoms, C₇-C₂₅aralkyl, orC₁-C₂₅alkoxy;R¹⁸ and R^(18′) independently of each other hydrogen, halogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one or more oxygen or sulphur atoms, C₇-C₂₅aralkyl, or C₁-C₂₅alkoxy;R¹⁹ is hydrogen, C₇-C₂₅aralkyl, C₆-C₁₈aryl; C₆-C₁₈aryl which issubstituted by C₁-C₁₈alkyl, or C₁-C₁₈alkoxy; or C₁-C₂₅alkyl, especiallyC₄-C₂₅alkyl, which may optionally be interrupted by one or more oxygenor sulphur atoms;R²⁰ and R^(20′) are independently of each other hydrogen, C₇-C₂₅aralkyl,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one, or more oxygen, or sulphur atoms, and Ar¹ is as above.R¹⁴, R^(14′), R¹⁷ and R^(17′) are preferably independently of each otherhydrogen or C₁-C₂₅alkyl; R¹⁸ and R^(18′) independently of each otherhydrogen, or C₁-C₂₅alkyl;R¹⁹ is C₁-C₂₅alkyl;R²⁰ and R^(20′) are independently of each other hydrogen or C₁-C₂₅alkyl,and Ar¹ is as defined above.

In a preferred embodiment of the present invention the polymer is acopolymer, comprising repeating units of formula *

A

COM¹

* (VII), especially a copolymer of formula

wherein A and COM¹ are as defined above; n is number which results in amolecular weight of 4,000 to 2,000,000 Daltons, more preferably 10,000to 1,000,000 and most preferably 10,000 to 100,000 Daltons. n is usuallyin the range of 4 to 1000, especially 4 to 200, very especially 5 to150.

In said embodiment A is preferably a repeating unit of formula (Ia),(Ib), (Ic), (Id), (Ie), (If), (Ig), (Ih), (Ii), (Ij), (Ik), (Il), (Im),(In), (Io), (Ip), (Iq), (Ir), (Is), (It), or (Iu) as defined above.

In said embodiment polymers are preferred, comprising one or more(repeating) unit(s) of the formula

whereinR¹ is a C₈-C₃₆alkyl group,R³ is hydrogen, halogen, C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which mayoptionally be interrupted by one or more oxygen or sulphur atoms,C₇-C₂₅aralkyl, or C₁-C₂₅alkoxy;R⁴, R^(4′) and R⁵ are independently of each other hydrogen, halogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one or more oxygen or sulphur atoms, C₇-C₂₅aralkyl, or C₁-C₂₅alkoxy;R⁷, R^(7′), R⁹ and R^(9′) are independently of each other hydrogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one, or more oxygen, or sulphur atoms; or C₇-C₂₅aralkyl,R⁸ is C₇-C₂₅aralkyl, C₆-C₁₈aryl; C₆-C₁₈aryl which is substituted byC₁-C₁₈alkyl, or C₁-C₁₈alkoxy;or C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally beinterrupted by one or more oxygen or sulphur atoms;R¹⁹ is C₇-C₂₅aralkyl, C₆-C₁₈aryl; C₆-C₁₈aryl which is substituted byC₁-C₁₈alkyl, or C₁-C₁₈alkoxy; or C₁-C₂₅alkyl, especially C₄-C₂₅alkyl,which may optionally be interrupted by one or more oxygen or sulphuratoms,one of X⁵ and X⁶ is N and the other is CR¹⁴,R¹⁴, R^(14′), R¹⁷ and R^(17′) are independently of each other hydrogen,halogen, C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally beinterrupted by one or more oxygen or sulphur atoms; C₇-C₂₅aralkyl, orC₁-C₂₅alkoxy,R¹⁸ and R^(18′) independently of each other hydrogen, halogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one or more oxygen or sulphur atoms, C₇-C₂₅aralkyl, or C₁-C₂₅alkoxy.

Compounds are more preferred, wherein

R³ is hydrogen, halogen, C₇-C₂₅aralkyl, or C₁-C₂₅alkyl;

R⁴, R^(4′) and R⁵ are independently of each other hydrogen, halogen,C₇-C₂₅aralkyl, or C₁-C₂₅alkyl;

R⁷, R^(7′), R⁹ and R^(9′) are independently of each other hydrogen,C₇-C₂₅aralkyl, or C₁-C₂₅alkyl;

R⁸ is C₁-C₂₅alkyl, or C₇-C₂₅aralkyl; R¹⁹ is C₁-C₂₅alkyl, orC₇-C₂₅aralkyl;

R¹⁴, R^(14′), R¹⁷ and R^(17′) are independently of each other hydrogen,halogen, C₇-C₂₅aralkyl, or C₁-C₂₅alkyl;

R¹⁸ and R^(18′) independently of each other hydrogen, halogen,C₇-C₂₅aralkyl, or C₁-C₂₅alkyl.

Compounds are most preferred, wherein

R³ is hydrogen or C₁-C₂₅alkyl;

R⁴, R^(4′) and R⁵ are independently of each other hydrogen, orC₁-C₂₅alkyl;

R⁷, R^(7′), R⁹ and R^(9′) are independently of each other hydrogen, orC₁-C₂₅alkyl;

R⁸ is C₁-C₂₅alkyl; R¹⁹ is C₁-C₂₅alkyl;

R¹⁴, R^(14′), R¹⁷ and R^(17′) are independently of each other hydrogen,or C₁-C₂₅alkyl;

R¹⁸ and R^(18′) independently of each other hydrogen, or C₁-C₂₅alkyl.

—COM¹- is preferably a repeating unit, which is selected from the groupof formula

Groups of formula

are more preferred, a group of formula

is most preferred.

The polymers of the present invention can comprise more than 2 differentrepeating units, such as, for example, repeating units A, B and D, whichare different from each other. If the polymers comprise repeating unitsof the formula

A-D

and

B-D

, they are preferably (random) copolymers of formula *

A-D

_(x)

B-D

_(y)*, wherein x=0.995 to 0.005, y=0.005 to 0.995, especially x=0.2 to0.8, y=0.8 to 0.2, and wherein x+y=1. A is a repeating unit of formula(I), B is a repeating unit —COM¹- and D is a repeating unit —COM¹-, withthe proviso that A, B and D are different from each other.

Copolymers of formula II can be obtained, for example, by the Suzukireaction. The condensation reaction of an aromatic boronate and ahalogenide, especially a bromide, commonly referred to as the “Suzukireaction”, is tolerant of the presence of a variety of organicfunctional groups as reported by N. Miyaura and A. Suzuki in ChemicalReviews, Vol. 95, pp. 457-2483 (1995). Preferred catalysts are2-dicyclohexylphosphino-2′,6′-di-alkoxybiphenyl/palladium(II)acetates,tri-alykl-phosphonium salts/palladium (0) derivatives andtri-alkylphosphine/palladium (0) derivatives. Especially preferredcatalysts are 2-dicyclohexylphosphino-2′,6′-di-methoxybiphenyl(sPhos)/palladium(II)acetate and, tri-tert-butylphosphoniumtetrafluoroborate ((t-Bu)₃P*HBF₄)/tris(dibenzylideneacetone)dipalladium(0) (Pd₂(dba)₃) and tri-tert-butylphosphine(t-Bu)₃P/tris(dibenzylideneacetone)dipalladium (0) (Pd₂(dba)₃). Thisreaction can be applied to preparing high molecular weight polymers andcopolymers.

To prepare polymers corresponding to formula II a dihalogenide offormula X¹⁰-A-X¹⁰ is reacted with an equimolar amount of a diboronicacid or diboronate corresponding to formulaX¹¹

COM¹

X¹¹, ora dihalogenide of formula X¹⁰

COM¹

X¹⁰ is reacted with an equimolar amount of a diboronic acid ordiboronate corresponding to formula X¹¹-A-X¹¹, wherein X¹⁰ is halogen,especially Br, and X¹¹ is independently in each occurrence —B(OH)₂,—B(OY¹)₂,

wherein Y¹ is independently in each occurrence a C₁-C₁₀alkyl group andY² is independently in each occurrence a C₂-C₁₀alkylene group, such as—CY³Y⁴—CY⁵Y⁶—, or —CY⁷Y⁸—CY⁹Y¹⁰—CY¹¹Y¹²—, wherein Y³, Y⁴, Y⁵, Y⁶, Y⁷,Y⁸, Y⁹, Y¹⁰, Y¹¹ and Y¹² are independently of each other hydrogen, or aC₁-C₁₀alkyl group, especially —C(CH₃)₂C(CH₃)₂—, —C(CH₃)₂CH₂C(CH₃)₂—, or—CH₂C(CH₃)₂CH₂—, and Y¹³ and Y¹⁴ are independently of each otherhydrogen, or a C₁-C₁₀alkyl group, in a solvent and in the presence of acatalyst. The reaction is typically conducted at about 0° C. to 180° C.in an aromatic hydrocarbon solvent such as toluene, xylene. Othersolvents such as dimethylformamide, dioxane, dimethoxyethan andtetrahydrofuran can also be used alone, or in mixtures with an aromatichydrocarbon. An aqueous base, preferably sodium carbonate orbicarbonate, potassium phosphate, potassium carbonate or bicarbonate isused as activation agent for the boronic acid, boronate and as the HBrscavenger. A polymerization reaction may take 0.2 to 100 hours. Organicbases, such as, for example, tetraalkylammonium hydroxide, and phasetransfer catalysts, such as, for example TBAB, can promote the activityof the boron (see, for example, Leadbeater & Marco; Angew. Chem. Int.Ed. Eng. 42 (2003) 1407 and references cited therein). Other variationsof reaction conditions are given by T. I. Wallow and B. M. Novak in J.Org. Chem. 59 (1994) 5034-5037; and M. Remmers, M. Schulze, and G.Wegner in Macromol. Rapid Commun. 17 (1996) 239-252. Controll ofmolecular weight is possible by using either an excess of dibromide,diboronic acid, or diboronate, or a chain terminator.

If desired, a monofunctional halide, boronate, such as, for example, amonofunctional aryl halide, or aryl boronate, may be used as achain-terminator in such reactions, which will result in the formationof a terminal aryl group:

It is possible to control the sequencing of the monomeric units in theresulting copolymer by controlling the order and composition of monomerfeeds in the Suzuki reaction.

The polymers of the present invention can also be synthesized by theStille coupling (see, for example, Babudri et al, J. Mater. Chem., 2004,14, 11-34; J. K. Stille, Angew. Chemie Int. Ed. Engl. 1986, 25, 508). Toprepare polymers corresponding to formula II a dihalogenide of formulaX¹⁰-A-X¹⁰ is reacted with an equimolar amount of an organo tin compoundcorresponding to formula X^(11′)

COM¹

X^(11′), or a dihalogenide of formula X¹⁰

COM¹

X¹⁰ is reacted with an equimolar amount of an organo tin compoundcorresponding to formula X^(11′)-A-X^(11′), wherein

X¹¹ is independently in each occurrence —SnR²⁰⁷R²⁰⁸R²⁰⁹, wherein R²⁰⁷,R²⁰⁸ and R²⁰⁹ are identical or different and are H or C₁-C₆alkyl, or twoof the groups R²⁰⁷, R²⁰⁸ and R²⁰⁹ form a ring and these groups areoptionally branched, in an inert solvent at a temperature in range from0° C. to 200° C. in the presence of a palladium-containing catalyst. Itmust be ensured here that the totality of all monomers used has a highlybalanced ratio of organotin functions to halogen functions. In addition,it may prove advantageous to remove any excess reactive groups at theend of the reaction by end-capping with monofunctional reagents. Inorder to carry out the process, the tin compounds and the halogencompounds are preferably introduced into one or more inert organicsolvents and stirred at a temperature of from 0 to 200° C., preferablyfrom 30 to 170° C. for a period of from 1 hour to 200 hours, preferablyfrom 5 hours to 150 hours. The crude product can be purified by methodsknown to the person skilled in the art and appropriate for therespective polymer, for example repeated re-precipitation or even bydialysis.

Suitable organic solvents for the process described are, for example,ethers, for example diethyl ether, dimethoxyethane, diethylene glycoldimethyl ether, tetrahydrofuran, dioxane, dioxolane, diisopropyl etherand tert-butyl methyl ether, hydrocarbons, for example hexane,isohexane, heptane, cyclohexane, benzene, toluene and xylene, alcohols,for example methanol, ethanol, 1-propanol, 2-propanol, ethylene glycol,1-butanol, 2-butanol and tert-butanol, ketones, for example acetone,ethyl methyl ketone and isobutyl methyl ketone, amides, for exampledimethylformamide (DMF), dimethylacetamide and N-methylpyrrolidone,nitriles, for example acetonitrile, propionitrile and butyronitrile, andmixtures thereof.

The palladium and phosphine components should be selected analogously tothe description for the Suzuki variant.

Alternatively, the polymers of the present invention can also besynthesized by the Negishi reaction using zinc reagents A-(ZnX²²)²,wherein X²² is halogen and halides, and COM¹-(X²³)₂, wherein X²³ ishalogen or triflate, or using A-(X²³)₂ and D-(ZnX²²)₂. Reference is, forexample, made to E. Negishi et al., Heterocycles 18 (1982) 117-22.

Alternatively, the polymers of the present invention can also besynthesized by the Hiyama) reaction using organosilicon reagentsA-(SiR²¹⁰R²¹¹R²¹²)₂, wherein R²¹⁰, R²¹¹ and R²¹² are identical ordifferent and are halogen, C₁-C₆alkyl and COM¹-(X²³)₂, wherein X²³ ishalogen or triflate, or using A-(X²³)₂ and COM¹-(siR²¹⁰R²¹¹R²¹²)₂.Reference is, for example, made to T. Hiyama et al., Pure Appl. Chem. 66(1994) 1471-1478 and T. Hiyama et al., Synlett (1991) 845-853.

Homopolymers of the type (A)_(n) can be obtained via Yamamoto couplingof dihalides X¹⁰-A-X¹⁰, where X¹⁰ is halogen, preferably bromide.Alternatively homopolymers of the type (A)_(n) can be obtained viaoxidative polymerization of units X¹⁰-A-X¹⁰, where X¹⁰ is hydrogen, e.g.with FeCl₃ as oxidizing agent.

The polymers, wherein R¹ and/or R² are hydrogen can be obtained by usinga protecting group which can be removed after polymerization (see, forexample, EP-A-0 648 770, EP-A-0 648 817, EP-A-0 742 255, EP-A-0 761 772,WO98/32802, WO98/45757, WO98/58027, WO99/01511, WO00/17275, WO00/39221,WO00/63297 and EP-A-1 086 984). Conversion of the pigment precursor intoits pigmentary form is carried out by means of fragmentation under knownconditions, for example thermally, optionally in the presence of anadditional catalyst, for example the catalysts described in WO00/36210.

An example of such a protecting group is group of formula

wherein L is any desired group suitable for imparting solubility.L is preferably a group of formula

wherein Z¹, Z² and Z³ are independently of each other C₁-C₆alkyl,Z⁴ and Z⁸ are independently of each other C₁-C₆alkyl, C₁-C₆alkylinterrupted by oxygen, sulfur or N(Z¹²)₂, or unsubstituted orC₁-C₆alkyl-, C₁-C₆alkoxy-, halo-, cyano- or nitro-substituted phenyl orbiphenyl,Z⁵, Z⁶ and Z⁷ are independently of each other hydrogen or C₁-C₆alkyl,Z⁹ is hydrogen, C₁-C₆alkyl or a group of formula

Z¹⁰ and Z¹¹ are each independently of the other hydrogen, C₁-C₆alkyl,C₁-C₆alkoxy, halogen, cyano, nitro, N(Z¹²)₂, or unsubstituted or halo-,cyano-, nitro-, C₁-C₆alkyl- or C₁-C₆alkoxy-substituted phenyl,Z¹² and Z¹³ are C₁-C₆alkyl, Z¹⁴ is hydrogen or C₁-C₆alkyl, and Z¹⁵ ishydrogen, C₁-C₆alkyl, or unsubstituted or C₁-C₆alkyl-substituted phenyl,Q is p,q-C₂-C₆alkylene unsubstituted or mono- or poly-substituted byC₁-C₆alkoxy, C₁-C₆alkylthio or C₂-C₁₂dialkylamino, wherein p and q aredifferent position numbers,X is a hetero atom selected from the group consisting of nitrogen,oxygen and sulfur, m′ being the number 0 when X is oxygen or sulfur andm being the number 1 when X is nitrogen, andL¹ and L² are independently of each other unsubstituted or mono- orpoly-C₁-C₁₂alkoxy-, —C₂-C₂₄dialkylamino-, —C₆-C₁₂aryloxy-,—C₆-C₁₂arylthio-, —C₇-C₂₄alkylarylamino- or—C₁₂-C₂₄diarylamino-substituted C₁-C₆alkyl or[-(p′,q′-C₂-C₆alkylene)-Z—]_(n′)—C₁-C₆alkyl, n′ being a number from 1 to1000, p′ and q′ being different position numbers, each Z independentlyof any others being a hetero atom oxygen, sulfur orC₁-C₁₂alkyl-substituted nitrogen, and it being possible forC₂-C₆alkylene in the repeating [—C₂-C₆alkylene-Z—] units to be the sameor different,and L₁ and L₂ may be saturated or unsaturated from one to ten times, maybe uninterrupted or interrupted at any location by from 1 to 10 groupsselected from the group consisting of —(C═O)— and —C₆H₄—, and may carryno further substituents or from 1 to 10 further substituents selectedfrom the group consisting of halogen, cyano and nitro. Most preferred Lis a group of formula

The synthesis of the compounds of formula Br-A-Br is described inWO08/000664, and WO09/047,104, or can be done in analogy to the methodsdescribed therein. The synthesis of N-aryl substituted compounds offormula Br-A-Br can be done in analogy to the methods described in U.S.Pat. No. 5,354,869 and WO03/022848.

Compounds of the formula

wherein a, a′, b, b′, c, c′, d, d′, R¹, R², Ar¹, Ar^(1′), Ar², Ar^(2′),Ar³, Ar^(3′), Ar⁴ and Ar^(4′) are as defined in claim 1, and X is ZnX¹²,—SnR²⁰⁷R²⁰⁸R²⁰⁹, wherein R²⁰⁷, R²⁰⁸ and R²⁰⁹ are identical or differentand are H or C₁-C₆alkyl, wherein two radicals optionally form a commonring and these radicals are optionally branched or unbranched and X¹² isa halogen atom, very especially I, or Br; or —OS(O)₂CF₃, —OS(O)₂-aryl,especially

OS(O)₂CH₃, —B(OH)₂, —B(OY¹)₂,

—BF₄Na, or —BF₄K, wherein Y¹ is independently in each occurrence aC₁-C₁₀alkyl group and Y² is independently in each occurrence aC₂-C₁₀alkylene group, such as —CY³Y⁴—CY⁵Y⁶—, or —CY⁷Y⁸—CY⁹Y¹⁰—CY¹¹Y¹²—,wherein Y³, Y⁴, Y⁵, Y⁶, Y⁷, Y⁸, Y⁹, Y¹⁰, Y¹¹ and Y¹² are independentlyof each other hydrogen, or a C₁-C₁₀alkyl group, especially—C(CH₃)₂C(CH₃)₂—, —C(CH₃)₂CH₂C(CH₃)₂—, or —CH₂C(CH₃)₂CH₂—, and Y¹³ andY¹⁴ are independently of each other hydrogen, or a C₁-C₁₀alkyl group;are new and form a further subject of the present invention.

A mixture containing a polymer of the present invention results in asemi-conducting layer comprising a polymer of the present invention(typically 5% to 99.9999% by weight, especially 20 to 85% by weight) andat least another material. The other material can be, but is notrestricted to a fraction of the same polymer of the present inventionwith different molecular weight, another polymer of the presentinvention, a semi-conducting polymer, organic small molecules, such as,for example, a compound of formula III, carbon nanotubes, a fullerenederivative, inorganic particles (quantum dots, quantum rods, quantumtripods, TiO₂, ZnO etc.), conductive particles (Au, Ag etc.), insulatormaterials like the ones described for the gate dielectric (PET, PSetc.).

Accordingly, the present invention also relates to an organicsemiconductor material, layer or component, comprising a polymeraccording to the present invention.

The polymers of the invention according to the present invention can beused as the semiconductor layer in semiconductor devices. Accordingly,the present invention also relates to semiconductor devices, comprisinga polymer of the present invention, or an organic semiconductormaterial, layer or component. The semiconductor device is especially anorganic photovoltaic (PV) device (solar cell), a photodiode, or anorganic field effect transistor.

There are numerous types of semiconductor devices. Common to all is thepresence of one or more semiconductor materials. Semiconductor deviceshave been described, for example, by S. M. Sze in Physics ofSemiconductor Devices, 2^(nd) edition, John Wiley and Sons, New York(1981). Such devices include rectifiers, transistors (of which there aremany types, including p-n-p, n-p-n, and thin-film transistors), lightemitting semiconductor devices (for example, organic light emittingdiodes in display applications or backlight in e.g. liquid crystaldisplays), photoconductors, current limiters, solar cells, thermistors,p-n junctions, field-effect diodes, Schottky diodes, and so forth. Ineach semiconductor device, the semiconductor material is combined withone or more metals, metal oxides, such as, for example, indium tin oxide(ITO), and/or insulators to form the device. Semiconductor devices canbe prepared or manufactured by known methods such as, for example, thosedescribed by Peter Van Zant in Microchip Fabrication, Fourth Edition,McGraw-Hill, New York (2000). In particular, organic electroniccomponents can be manufactured as described by D. R. Gamota et al. inPrinted Organic and Molecular Electronics, Kluver Academic Publ.,Boston, 2004.

A particularly useful type of transistor device, the thin-filmtransistor (TFT), generally includes a gate electrode, a gate dielectricon the gate electrode, a source electrode and a drain electrode adjacentto the gate dielectric, and a semiconductor layer adjacent to the gatedielectric and adjacent to the source and drain electrodes (see, forexample, S. M. Sze, Physics of Semiconductor Devices, 2^(nd) edition,John Wiley and Sons, page 492, New York (1981)). These components can beassembled in a variety of configurations. More specifically, an OFET hasan organic semiconductor layer.

Typically, a substrate supports the OFET during manufacturing, testing,and/or use. Optionally, the substrate can provide an electrical functionfor the OFET. Useful substrate materials include organic and inorganicmaterials. For example, the substrate can comprise silicon materialsinclusive of various appropriate forms of silicon, inorganic glasses,ceramic foils, polymeric materials (for example, acrylics, polyester,epoxies, polyamides, polycarbonates, polyimides, polyketones,poly(oxy-1,4-phenyleneoxy-1,4-phenylenecarbonyl-1,4-phenylene)(sometimes referred to as poly(ether ether ketone) or PEEK),polynorbornenes, polyphenyleneoxides, poly(ethylenenaphthalenedicarboxylate) (PEN), poly(ethylene terephthalate) (PET),poly(phenylene sulfide) (PPS)), filled polymeric materials (for example,fiber-reinforced plastics (FRP)), and coated metallic foils.

The gate electrode can be any useful conductive material. For example,the gate electrode can comprise doped silicon, or a metal, such asaluminum, chromium, gold, silver, nickel, palladium, platinum, tantalum,and titanium. Conductive oxides, such as indium tin oxide, or conductinginks/pastes comprised of carbon black/graphite or colloidal silverdispersions, optionally containing polymer binders can also be used.Conductive polymers also can be used, for example polyaniline orpoly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate) (PEDOT:PSS). Inaddition, alloys, combinations, and multilayers of these materials canbe useful. In some OFETs, the same material can provide the gateelectrode function and also provide the support function of thesubstrate. For example, doped silicon can function as the gate electrodeand support the OFET.

The gate dielectric is generally provided on the gate electrode. Thisgate dielectric electrically insulates the gate electrode from thebalance of the OFET device. Useful materials for the gate dielectric cancomprise, for example, an inorganic electrically insulating material.

The gate dielectric (insulator) can be a material, such as, an oxide,nitride, or it can be a material selected from the family offerroelectric insulators (e.g. organic materials such as poly(vinylidenefluoride/trifluoroethylene or poly(m-xylylene adipamide)), or it can bean organic polymeric insulator (e.g. poly(methacrylate)s,poly(acrylate)s, polyimides, benzocyclobutenes (BCBs), parylenes,polyvinylalcohol, polyvinylphenol (PVP), polystyrenes, polyester,polycarbonates) as for example described in J. Veres et al. Chem. Mat.2004, 16, 4543 or A. Facchetti et al. Adv. Mat. 2005, 17, 1705. Specificexamples of materials useful for the gate dielectric includestrontiates, tantalates, titanates, zirconates, aluminum oxides, siliconoxides, tantalum oxides, titanium oxides, silicon nitrides, bariumtitanate, barium strontium titanate, barium zirconate titanate, zincselenide, and zinc sulphide, including but not limited toPbZr_(x)Ti_(1-X)O₃ (PZT), Bi₄Ti₃O₁₂, BaMgF₄, Ba(Zr_(1-x)Ti_(x))O₃ (BZT).In addition, alloys, hybride materials (e.g. polysiloxanes ornanoparticle-filled polymers) combinations, and multilayers of thesematerials can be used for the gate dielectric. The thickness of thedielectric layer is, for example, from about 10 to 1000 nm, with a morespecific thickness being about 100 to 500 nm, providing a capacitance inthe range of 0.1-100 nanofarads (nF).

The source electrode and drain electrode are separated from the gateelectrode by the gate dielectric, while the organic semiconductor layercan be over or under the source electrode and drain electrode. Thesource and drain electrodes can be any useful conductive materialfavourably providing a low resistance ohmic contact to the semiconductorlayer. Useful materials include most of those materials described abovefor the gate electrode, for example, aluminum, barium, calcium,chromium, gold, silver, nickel, palladium, platinum, titanium,polyaniline, PEDOT:PSS, other conducting polymers, alloys thereof,combinations thereof, and multilayers thereof. Some of these materialsare appropriate for use with n-type semiconductor materials and othersare appropriate for use with p-type semiconductor materials, as is knownin the art.

The thin film electrodes (that is, the gate electrode, the sourceelectrode, and the drain electrode) can be provided by any useful meanssuch as physical vapor deposition (for example, thermal evaporation orsputtering) or (ink jet) printing methods. The patterning of theseelectrodes can be accomplished by known methods such as shadow masking,additive photolithography, subtractive photolithography, printing,microcontact printing, and pattern coating.

The present invention further provides an organic field effecttransistor device comprising

a plurality of electrically conducting gate electrodes disposed on asubstrate;

a gate insulator layer disposed on said electrically conducting gateelectrodes;

a plurality of sets of electrically conductive source and drainelectrodes disposed on said insulator layer such that each of said setsis in alignment with each of said gate electrodes;

an organic semiconductor layer disposed in the channel between sourceand drain electrodes on said insulator layer substantially overlappingsaid gate electrodes; wherein

said organic semiconductor layer comprises a polymer of the presentinvention, or an organic semiconductor material, layer or component.

The present invention further provides a process for preparing a thinfilm transistor device comprising the steps of:

depositing a plurality of electrically conducting gate electrodes on asubstrate;

depositing a gate insulator layer on said electrically conducting gateelectrodes;

depositing a plurality of sets of electrically conductive source anddrain electrodes on said layer such that each of said sets is inalignment with each of said gate electrodes;

depositing a layer of a polymer of the present invention on saidinsulator layer such that said layer of the polymer of the presentinvention, or a mixture containing a polymer of the present invention,substantially overlaps said gate electrodes; thereby producing the thinfilm transistor device.

Alternatively, an OFET is fabricated by, for example, by solutiondeposition of a polymer on a highly doped silicon substrate covered witha thermally grown oxide layer followed by vacuum deposition andpatterning of source and drain electrodes.

In yet another approach, an OFET is fabricated by deposition of sourceand drain electrodes on a highly doped silicon substrate covered with athermally grown oxide and then solution deposition of the polymer toform a thin film.

The gate electrode could also be a patterned metal gate electrode on asubstrate or a conducting material such as, a conducting polymer, whichis then coated with an insulator applied either by solution coating orby vacuum deposition on the patterned gate electrodes.

Any suitable solvent can be used to dissolve, and/or disperse thepolymers of the present application, provided it is inert and can beremoved partly, or completely from the substrate by conventional dryingmeans (e.g. application of heat, reduced pressure, airflow etc.).Suitable organic solvents for processing the semiconductors of theinvention include, but are not limited to, aromatic or aliphatichydrocarbons, halogenated such as chlorinated or fluorinatedhydrocarbons, esters, ethers, amides, such as chloroform,tetrachloroethane, tetrahydrofuran, toluene, tetraline, decaline,anisole, xylene, ethyl acetate, methyl ethyl ketone, dimethyl formamide,chloroform, chlorobenzene, dichlorobenzene, trichlorobenzene, propyleneglycol monomethyl ether acetate (PGMEA) and mixtures thereof. Preferredsolvents are xylene, toluene, tetraline, decaline, chlorinated ones suchas chloroform, chlorobenzene, ortho-dichlorobenzene, trichlorobenzeneand mixtures thereof. The solution, and/or dispersion is then applied bya method, such as, spin-coating, dip-coating, screen printing,microcontact printing, doctor blading or other solution applicationtechniques known in the art on the substrate to obtain thin films of thesemiconducting material.

The term “dispersion” covers any composition comprising thesemiconductor material of the present invention, which is not fullydissolved in a solvent. The dispersion can be done selecting acomposition including at least a polymer of the present invention, or amixture containing a polymer of the present invention, and a solvent,wherein the polymer exhibits lower solubility in the solvent at roomtemperature but exhibits greater solubility in the solvent at anelevated temperature, wherein the composition gels when the elevatedtemperature is lowered to a first lower temperature without agitation;

-   -   dissolving at the elevated temperature at least a portion of the        polymer in the solvent; lowering the temperature of the        composition from the elevated temperature to the first lower        temperature; agitating the composition to disrupt any gelling,        wherein the agitating commences at any time prior to,        simultaneous with, or subsequent to the lowering the elevated        temperature of the composition to the first lower temperature;        depositing a layer of the composition wherein the composition is        at a second lower temperature lower than the elevated        temperature; and drying at least partially the layer.

The dispersion can also be constituted of (a) a continuous phasecomprising a solvent, a binder resin, and optionally a dispersing agent,and (b) a disperse phase comprising a polymer of the present invention,or a mixture containing a polymer of the present invention. The degreeof solubility of the polymer of the present invention in the solvent mayvary for example from 0% to about 20% solubility, particularly from 0%to about 5% solubility.

Preferably, the thickness of the organic semiconductor layer is in therange of from about 5 to about 1000 nm, especially the thickness is inthe range of from about 10 to about 100 nm.

The polymers of the invention can be used alone or in combination as theorganic semiconductor layer of the semiconductor device. The layer canbe provided by any useful means, such as, for example, vapor deposition(for materials with relatively low molecular weight) and printingtechniques. The compounds of the invention may be sufficiently solublein organic solvents and can be solution deposited and patterned (forexample, by spin coating, dip coating, ink jet printing, gravureprinting, flexo printing, offset printing, screen printing, microcontact(wave)-printing, drop or zone casting, or other known techniques).

The polymers of the invention can be used in integrated circuitscomprising a plurality of OTFTs, as well as in various electronicarticles. Such articles include, for example, radio-frequencyidentification (RFID) tags, backplanes for flexible displays (for usein, for example, personal computers, cell phones, or handheld devices),smart cards, memory devices, sensors (e.g. light-, image-, bio-, chemo-,mechanical- or temperature sensors), especially photodiodes, or securitydevices and the like. Due to its ambi-polarity the material can also beused in Organic Light Emitting Transistors (OLET).

A further aspect of the present invention is an organic semiconductormaterial, layer or component comprising one or more polymers of thepresent invention. A further aspect is the use of the polymers ormaterials of the present invention in an organic photovoltaic (PV)device (solar cell), a photodiode, or an organic field effect transistor(OFET). A further aspect is an organic photovoltaic (PV) device (solarcell), a photodiode, or an organic field effect transistor (OFET)comprising a polymer or material of the present invention.

The polymers of the present invention are typically used as organicsemiconductors in form of thin organic layers or films, preferably lessthan 30 microns thick. Typically the semiconducting layer of the presentinvention is at most 1 micron (=1 μm) thick, although it may be thickerif required. For various electronic device applications, the thicknessmay also be less than about 1 micron thick. For example, for use in anOFET the layer thickness may typically be 100 nm or less. The exactthickness of the layer will depend, for example, upon the requirementsof the electronic device in which the layer is used.

For example, the active semiconductor channel between the drain andsource in an OFET may comprise a layer of the present invention.

An OFET device according to the present invention preferably comprises:

-   -   a source electrode,    -   a drain electrode,    -   a gate electrode,    -   a semiconducting layer,    -   one or more gate insulator layers, and    -   optionally a substrate, wherein the semiconductor layer        comprises one or more polymers of the present invention.

The gate, source and drain electrodes and the insulating andsemiconducting layer in the OFET device may be arranged in any sequence,provided that the source and drain electrode are separated from the gateelectrode by the insulating layer, the gate electrode and thesemiconductor layer both contact the insulating layer, and the sourceelectrode and the drain electrode both contact the semiconducting layer.

Preferably the OFET comprises an insulator having a first side and asecond side, a gate electrode located on the first side of theinsulator, a layer comprising a polymer of the present invention locatedon the second side of the insulator, and a drain electrode and a sourceelectrode located on the polymer layer.

The OFET device can be a top gate device or a bottom gate device.

Suitable structures and manufacturing methods of an OFET device areknown to the skilled in the art and are described in the literature, forexample in WO03/052841.

The gate insulator layer may comprise for example a fluoropolymer, likee.g. the commercially available Cytop 809M®, or Cytop 107M® (from AsahiGlass). Preferably the gate insulator layer is deposited, e.g. byspin-coating, doctor blading, wire bar coating, spray or dip coating orother known methods, from a formulation comprising an insulator materialand one or more solvents with one or more fluoro atoms (fluorosolvents),preferably a perfluorosolvent. A suitable perfluorosolvent is e.g. FC75®(available from Acros, catalogue number 12380). Other suitablefluoropolymers and fluorosolvents are known in prior art, like forexample the perfluoropolymers Teflon AF® 1600 or 2400 (from DuPont), orFluoropel® (from Cytonix) or the perfluorosolvent FC 43® (Acros, No.12377).

The semiconducting layer comprising a polymer of the present inventionmay additionally comprise at least another material. The other materialcan be, but is not restricted to another polymer of the presentinvention, a semi-conducting polymer, a polymeric binder, organic smallmolecules different from a polymer of the present invention, carbonnanotubes, a fullerene derivative, inorganic particles (quantum dots,quantum rods, quantum tripods, TiO₂, ZnO etc.), conductive particles(Au, Ag etc.), and insulator materials like the ones described for thegate dielectric (PET, PS etc.). As stated above, the semiconductivelayer can also be composed of a mixture of one or more polymers of thepresent invention and a polymeric binder. The ratio of the polymers ofthe present invention to the polymeric binder can vary from 5 to 95percent. Preferably, the polymeric binder is a semicristalline polymersuch as polystyrene (PS), high-density polyethylene (HDPE),polypropylene (PP) and polymethylmethacrylate (PMMA). With thistechnique, a degradation of the electrical performance can be avoided(cf. WO2008/001123A1).

The polymers of the present invention are advantageously used in organicphotovoltaic (PV) devices (solar cells). Accordingly, the inventionprovides PV devices comprising a polymer according to the presentinvention. A device of this construction will also have rectifyingproperties so may also be termed a photodiode. Photoresponsive deviceshave application as solar cells which generate electricity from lightand as photodetectors which measure or detect light.

The PV device comprise in this order:

(a) a cathode (electrode),

(b) optionally a transition layer, such as an alkali halogenide,especially lithium fluoride,

(c) a photoactive layer,

(d) optionally a smoothing layer,

(e) an anode (electrode),

(f) a substrate.

The photoactive layer comprises the polymers of the present invention.Preferably, the photoactive layer is made of a conjugated polymer of thepresent invention, as an electron donor and an acceptor material, like afullerene, particularly a functionalized fullerene PCBM, as an electronacceptor. For heterojunction solar cells the active layer comprisespreferably a mixture of a polymer of the present invention and afullerene, such as [60]PCBM (=6,6-phenyl-C₆₁-butyric acid methyl ester),or [70]PCBM, in a weight ratio of 1:1 to 1:3.

The structure and the components of the photovoltaic device aredescribed in more detail below.

In a further embodiment the present invention relates to compounds ofthe formula

wherein a, a′, b, b′, c, c′, d, d′, R¹, R², Ar¹, Ar^(1′), Ar², Ar^(2′),Ar³, Ar^(3′), Ar⁴ and Ar^(4′) are as defined above,R¹⁰ and R^(10′) are independently of each other hydrogen, halogen,C₁-C₂₅alkyl, C₁-C₂₅alkoxy, or a group of one of the formulae IVa to IVi,

wherein R²² to R²⁶ and R²⁹ to R⁵⁸ represent independently of each otherH, halogen, C₁-C₂₅alkyl, C₁-C₂₅alkyl which is substituted by E and/orinterrupted by D, C₆-C₂₄aryl, C₆-C₂₄aryl which is substituted by G,C₂-C₂₀heteroaryl, C₂-C₂₀heteroaryl which is substituted by G, aC₄-C₁₈cycloalkyl group, a C₄-C₁₈cycloalkyl group, which is substitutedby G, C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₁-C₁₈alkoxy, C₁-C₁₈alkoxy which issubstituted by E and/or interrupted by D, C₇-C₂₅aralkyl, orC₇-C₂₅aralkyl, which is substituted by G,R²⁷ and R²⁸ are independently of each other hydrogen, C₁-C₂₅alkyl, orC₇-C₂₅aralkyl, or R²⁷ and R²⁸ together represent alkylene or alkenylenewhich may be both bonded via oxygen and/or sulfur to the thienyl residueand which may both have up to 25 carbon atoms,D is —CO—, —COO—, —S—, —O—, or NR¹¹²—,E is C₁-C₈thioalkoxy, C₁-C₈alkoxy, CN, —NR¹¹²R¹¹³, —CONR¹¹²R¹¹³, orhalogen,G is E, or C₁-C₁₈alkyl, andR¹¹² and R¹¹³ are independently of each other H; C₆-C₁₈aryl; C₆-C₁₈arylwhich is substituted by C₁-C₁₈alkyl, or C₁-C₁₈alkoxy; C₁-C₁₈alkyl; orC₁-C₁₈alkyl which is interrupted by —O—; with the proviso that thefollowing compound

is excluded.

Preferably, R¹⁹ and R^(10′) are independently of each other hydrogen,C₁-C₂₅alkyl or a group of one of the formulae IVb, or VIc, wherein R²²to R²⁶ and R²⁹ to R⁵⁸ represent independently of each other hydrogen, orC₁-C₂₅alkyl.

In a preferred embodiment of the present invention Ar¹ and Ar^(1′) areselected from groups of formula Xa, Xb, Xc, Xd, and Xg, especially Xa,Xc and Xg. In another preferred embodiment of the present invention Ar¹and Ar^(1′) are selected from groups of formula Xe, Xf, Xh, Xi, Xj, Xk,Xm, Xn, Xq, Xr, Xv, Xx, Xy, XIa, XIb, XIg, XIh, XIi and XIl, especiallyXe, Xj, Xm, Xn, Xr, Xv, Xx, XIb and XIi.

In said embodiment compounds of formula

are more preferred, whereinR′ is a C₈-C₃₆alkyl group,R³ and R^(3′) are independently of each other hydrogen, halogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one or more oxygen or sulphur atoms, or C₁-C₂₅alkoxy; R^(3″) has themeaning of R³;R¹⁰⁴ and R^(104′) are independently of each other hydrogen, halogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one or more oxygen or sulphur atoms, or C₁-C₂₅alkoxy;R⁴, R^(4′), R⁵, and R^(5′) are independently of each other hydrogen,halogen, C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally beinterrupted by one or more oxygen or sulphur atoms, or C₁-C₂₅alkoxy;R⁷, R^(7′), R⁹ and R^(9′) are independently of each other hydrogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one, or more oxygen, or sulphur atoms,R⁸ is C₆-C₁₈aryl; C₆-C₁₈aryl which is substituted by C₁-C₁₈alkyl, orC₁-C₁₈alkoxy; or C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which mayoptionally be interrupted by one or more oxygen or sulphur atoms,R¹² and R^(12′) are independently of each other hydrogen, halogen,C₁-C₂₅alkyl, especially C₄-C₂₅alkyl, which may optionally be interruptedby one, or more oxygen, or sulphur atoms, C₁-C₂₅alkoxy, or

R¹³, wherein R¹³ is a C₁-C₁₀alkyl group, or a tri(C₁-C₈alkyl)silylgroup, and R¹⁹ is hydrogen, C₁-C₂₅alkyl or a group of one of theformulae IVb, or VIc, wherein R²² to R²⁶ and R²⁹ to R⁵⁸ representindependently of each other hydrogen, or C₁-C₂₅alkyl

In said embodiment of the present invention compounds of the formulasIIIa, IIIb, IIIc, IIIe, IIIg, IIIi, IIIj, IIIk and IIIl are preferred,compounds of the formulas IIIa, IIIb, IIIc, IIIe, IIIj and IIIl are morepreferred, and compounds of the formula IIIe are most preferred, wherein

R¹ is C₈-C₃₆alkyl,

R³ is hydrogen, halogen or C₁-C₂₅alkyl;

R⁴, R^(4′), R⁵, R^(5′) and R⁶ are independently of each other hydrogen,halogen, or C₁-C₂₅alkyl;

R⁷, R^(7′), R⁹ and R^(9′) are independently of each other hydrogen, orC₁-C₂₅alkyl;

R⁸ is C₁-C₂₅alkyl, especially C₄-C₂₅alkyl.

The process for the preparation of a compound of the formula IIIcomprises

(a) reacting (in the presence of a strong base) one mole of adisuccinate, like dimethyl succinate, with 1 mole of a nitrile of theformulaR¹⁰

Ar⁴

_(d)

Ar³

_(c)

Ar²

_(b)

Ar¹

_(a)≡N

-   -   and 1 mole of a nitrile of the formula        N≡        Ar^(1′)        _(a′)        Ar^(2′)        _(b′)        Ar^(3′)        _(c′)        Ar^(4′)        _(d′)R^(10′),        (b) optionally reacting a compound of formula

obtained in step a) with a compound of the formula R¹-Hal, wherein Halis halogen, —O-mesylate, or O-tosylate, preferably bromide or iodide, inthe presence of a suitable base, like potassium carbonate, in a suitablesolvent, like N-methyl-pyrrolidone, wherein R¹⁰ and R^(10′) are asdefined above, and(c) optionally reacting a compound of formula

obtained in step b), wherein R¹⁰ and R^(10′) are hydrogen, with asuitable brominating agent, like N-bromo-succinimide, wherein a, a′, b,b′, c, c′, d, d′, R¹, R², Ar¹, Ar^(1′), Ar², Ar^(2′), Ar³, Ar^(3′), Ar⁴and Ar^(4′) are as defined above.

The compounds of the formula III can be manufactured by known methods.Reference is, for example, made to pages 16 to 20 of WO09/047,104.

Compounds of the formula VI can be obtained as described in U.S. Pat.No. 4,579,949 by reacting (in the presence of a strong base) one mole ofa disuccinate, like dimethyl succinate, with 1 mole of a nitrile of theformulae R¹⁰

Ar⁴

_(d)

Ar³

_(c)

Ar²

_(b)

Ar¹

_(a)≡N and 1 mole of a nitrile of the formula N≡

Ar^(1′)

_(a′)

Ar^(2′)

_(b′)

Ar^(3′)

_(c′)

Ar^(4′)

_(d′)R^(10′). Symmetrical compounds of the formula VI are obtained byreacting (in the presence of a strong base) one mole of a disuccinate,like dimethyl succinate, with 2 mole of a nitrile of the formulaR¹⁰

Ar⁴

_(d)

Ar³

_(c)

Ar²

_(b)

Ar¹

_(a)≡N

Alternatively, said compounds of formulae VI can be obtained asdescribed in U.S. Pat. No. 4,659,775 by reacting a nitrile with asuitable ester, like a pyrrolinon-3-carboxylic ester derivative.

The compound of the formula VI is N-alkylated for introduction of thegroup R¹, e.g. by reaction with a bromide of the formula R¹—Br in thepresence of a suitable base, like potassium carbonate, in a suitablesolvent, like N-methyl-pyrrolidone. The reaction is carried out at atemperature from about room temperature to about 180° C., preferablyfrom about 100° C. to about 170° C., e.g. at 140° C.

The thus obtained compound of the formula VII is then reacted with asuitable brominating agent, like N-bromo-succinimide, to yield acompound of the formulae VI, respectively. The bromination is carriedout in a suitable solvent, like chloroform, using two equivalents ofN-bromo-succinimide at a temperature between −30° C. and +50° C.,preferably between −10° C. and room temperature, e.g. at 0° C.

Advantageously, the compound of formula III, or an organic semiconductormaterial, layer or component, comprising the compound of formula III canbe used in organic photovoltaics (solar cells) and photodiodes, or in anorganic field effect transistor (OFET).

A mixture containing the compound of formula III results in asemi-conducting layer comprising the compound of formula III (typically5% to 99.9999% by weight, especially 20 to 85% by weight) and at leastanother material. The other material can be, but is not restricted toanother compound of formula III, a polymer of the present invention, asemi-conducting polymer, a non-conductive polymer, organic smallmolecules, carbon nanotubes, a fullerene derivative, inorganic particles(quantum dots, quantum rods, quantum tripods, TiO₂, ZnO etc.),conductive particles (Au, Ag etc.), insulator materials like the onesdescribed for the gate dielectric (PET, PS etc.).

Accordingly, the present invention also relates to an organicsemiconductor material, layer or component, comprising a compound offormula III and to a semiconductor device, comprising a compound offormula III and/or an organic semiconductor material, layer orcomponent.

The semiconductor is preferably an organic photovoltaic (PV) device(solar cell), a photodiode, or an organic field effect transistor. Thestructure and the components of the OFET device has been described inmore detail above.

Accordingly, the invention provides organic photovoltaic (PV) devices(solar cells) comprising a compound of the formula III.

The PV device comprise in this order:

(a) a cathode (electrode),

(b) optionally a transition layer, such as an alkali halogenide,especially lithium fluoride,

(c) a photoactive layer,

(d) optionally a smoothing layer,

(e) an anode (electrode),

(f) a substrate.

The photoactive layer comprises the compounds of the formula III.Preferably, the photoactive layer is made of a compound of the formulaIII, as an electron donor and an acceptor material, like a fullerene,particularly a functionalized fullerene PCBM, as an electron acceptor.As stated above, the photoactive layer may also contain a polymericbinder. The ratio of the small molecules of formula III to the polymericbinder can vary from 5 to 95 percent. Preferably, the polymeric binderis a semicristalline polymer such as polystyrene (PS), high-densitypolyethylene (HDPE), polypropylene (PP) and polymethylmethacrylate(PMMA).

The fullerenes useful in this invention may have a broad range of sizes(number of carbon atoms per molecule). The term fullerene as used hereinincludes various cage-like molecules of pure carbon, includingBuckminsterfullerene (C₆₀) and the related “spherical” fullerenes aswell as carbon nanotubes. Fullerenes may be selected from those known inthe art ranging from, for example, C₂₀-C₁₀₀₀. Preferably, the fullereneis selected from the range of C₆₀ to C₉₆. Most preferably the fullereneis C₆₀ or C₇₀, such as [60]PCBM, or [70]PCBM. It is also permissible toutilize chemically modified fullerenes, provided that the modifiedfullerene retains acceptor-type and electron mobility characteristics.The acceptor material can also be a material selected from the groupconsisting of another compounds of formula III, or any semi-conductingpolymer, such as, for example, a polymer of formula I, provided that thepolymers retain acceptor-type and electron mobility characteristics,organic small molecules, carbon nanotubes, inorganic particles (quantumdots, quantum rods, quantum tripods, TiO₂, ZnO etc.).

The photoactive layer is made of a compound of the formula III, as anelectron donor and a fullerene, particularly functionalized fullerenePCBM, as an electron acceptor. These two components are mixed with asolvent and applied as a solution onto the smoothing layer by, forexample, the spin-coating method, the drop casting method, theLangmuir-Blodgett (“LB”) method, the ink jet printing method and thedripping method. A squeegee or printing method could also be used tocoat larger surfaces with such a photoactive layer. Instead of toluene,which is typical, a dispersion agent such as chlorobenzene is preferablyused as a solvent. Among these methods, the vacuum deposition method,the spin-coating method, the ink jet printing method and the castingmethod are particularly preferred in view of ease of operation and cost.

In the case of forming the layer by using the spin-coating method, thecasting method and ink jet printing method, the coating can be carriedout using a solution and/or dispersion prepared by dissolving, ordispersing the composition in a concentration of from 0.01 to 90% byweight in an appropriate organic solvent such as benzene, toluene,xylene, tetrahydrofurane, methyltetrahydrofurane, N,N-dimethylformamide,acetone, acetonitrile, anisole, dichloromethane, dimethylsulfoxide,chlorobenzene, 1,2-dichlorobenzene and mixtures thereof.

The photovoltaic (PV) device can also consist of multiple junction solarcells that are processed on top of each other in order to absorb more ofthe solar spectrum. Such structures are, for example, described in App.Phys. Let. 90, 143512 (2007), Adv. Funct. Mater. 16, 1897-1903 (2006)and WO2004/112161.

A so called ‘tandem solar cell’ comprise in this order:

(a) a cathode (electrode),

(b) optionally a transition layer, such as an alkali halogenide,especially lithium fluoride,

(c) a photoactive layer,

(d) optionally a smoothing layer,

(e) a middle electrode (such as Au, Al, ZnO, TiO₂ etc.)

(f) optionally an extra electrode to match the energy level,

(g) optionally a transition layer, such as an alkali halogenide,especially lithium fluoride,

(h) a photoactive layer,

(i) optionally a smoothing layer,

(j) an anode (electrode),

(k) a substrate.

The PV device can also be processed on a fiber as described, forexample, in US20070079867 and US 20060013549.

Due to their excellent self-organising properties the materials or filmscomprising the compounds of the formula III can also be used alone ortogether with other materials in or as alignment layers in LCD or OLEDdevices, as described for example in US2003/0021913.

An OFET device according to the present invention preferably comprises:

-   -   a source electrode,    -   a drain electrode,    -   a gate electrode,    -   a semiconducting layer,    -   one or more gate insulator layers, and    -   optionally a substrate, wherein the semiconductor layer        comprises a compound of formula III.

The gate, source and drain electrodes and the insulating andsemiconducting layer in the OFET device may be arranged in any sequence,provided that the source and drain electrode are separated from the gateelectrode by the insulating layer, the gate electrode and thesemiconductor layer both contact the insulating layer, and the sourceelectrode and the drain electrode both contact the semiconducting layer.

Preferably the OFET comprises an insulator having a first side and asecond side, a gate electrode located on the first side of theinsulator, a layer comprising a compound of formula III located on thesecond side of the insulator, and a drain electrode and a sourceelectrode located on the polymer layer.

C₁-C₂₅alkyl (C₁-C₁₈alkyl) is typically linear or branched, wherepossible. Examples are methyl, ethyl, n-propyl, isopropyl, n-butyl,sec.-butyl, isobutyl, tert.-butyl, n-pentyl, 2-pentyl, 3-pentyl,2,2-dimethylpropyl, 1,1,3,3-tetramethylpentyl, n-hexyl, 1-methylhexyl,1,1,3,3,5,5-hexamethylhexyl, n-heptyl, isoheptyl,1,1,3,3-tetramethylbutyl, 1-methylheptyl, 3-methylheptyl, n-octyl,1,1,3,3-tetramethylbutyl and 2-ethylhexyl, n-nonyl, decyl, undecyl,dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl,octadecyl, eicosyl, heneicosyl, docosyl, tetracosyl or pentacosyl.C₁-C₈alkyl is typically methyl, ethyl, n-propyl, isopropyl, n-butyl,sec.-butyl, isobutyl, tert.-butyl, n-pentyl, 2-pentyl, 3-pentyl,2,2-dimethyl-propyl, n-hexyl, n-heptyl, n-octyl,1,1,3,3-tetramethylbutyl and 2-ethylhexyl. C₁-C₄alkyl is typicallymethyl, ethyl, n-propyl, isopropyl, n-butyl, sec.-butyl, isobutyl,tert.-butyl.

C₁-C₂₅alkoxy (C₁-C₁₈alkoxy) groups are straight-chain or branched alkoxygroups, e.g. methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy,sec-butoxy, tert-butoxy, amyloxy, isoamyloxy or tert-amyloxy, heptyloxy,octyloxy, isooctyloxy, nonyloxy, decyloxy, undecyloxy, dodecyloxy,tetradecyloxy, pentadecyloxy, hexadecyloxy, heptadecyloxy andoctadecyloxy. Examples of C₁-C₈alkoxy are methoxy, ethoxy, n-propoxy,isopropoxy, n-butoxy, sec.-butoxy, isobutoxy, tert.-butoxy, n-pentoxy,2-pentoxy, 3-pentoxy, 2,2-dimethylpropoxy, n-hexoxy, n-heptoxy,n-octoxy, 1,1,3,3-tetramethylbutoxy and 2-ethylhexoxy, preferablyC₁-C₄alkoxy such as typically methoxy, ethoxy, n-propoxy, isopropoxy,n-butoxy, sec.-butoxy, isobutoxy, tert.-butoxy. The term “alkylthiogroup” means the same groups as the alkoxy groups, except that theoxygen atom of the ether linkage is replaced by a sulfur atom.

C₂-C₂₅alkenyl (C₂-C₁₈alkenyl) groups are straight-chain or branchedalkenyl groups, such as e.g. vinyl, allyl, methallyl, isopropenyl,2-butenyl, 3-butenyl, isobutenyl, n-penta-2,4-dienyl,3-methyl-but-2-enyl, n-oct-2-enyl, n-dodec-2-enyl, isododecenyl,n-dodec-2-enyl or n-octadec-4-enyl.

C₂₋₂₄alkynyl (C₂₋₁₈alkynyl) is straight-chain or branched and preferablyC₂₋₈alkynyl, which may be unsubstituted or substituted, such as, forexample, ethynyl, 1-propyn-3-yl, 1-butyn-4-yl, 1-pentyn-5-yl,2-methyl-3-butyn-2-yl, 1,4-pentadiyn-3-yl, 1,3-pentadiyn-5-yl,1-hexyn-6-yl, cis-3-methyl-2-penten-4-yn-1-yl,trans-3-methyl-2-penten-4-yn-1-yl, 1,3-hexadiyn-5-yl, 1-octyn-8-yl,1-nonyn-9-yl, 1-decyn-10-yl, or 1-tetracosyn-24-yl.

C₅-C₁₂cycloalkyl is typically cyclopentyl, cyclohexyl, cycloheptyl,cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl, cyclododecyl,preferably cyclopentyl, cyclohexyl, cycloheptyl, or cyclooctyl, whichmay be unsubstituted or substituted. The cycloalkyl group, in particulara cyclohexyl group, can be condensed one or two times by phenyl whichcan be substituted one to three times with C₁-C₄-alkyl, halogen andcyano. Examples of such condensed cyclohexyl groups are:

in particular

wherein R¹⁵¹, R¹⁵², R¹⁵³, R¹⁵⁴, R¹⁵⁵ and R¹⁵⁶ are independently of eachother C₁-C₈-alkyl, C₁-C₈-alkoxy, halogen and cyano, in particularhydrogen.

C₆-C₂₄aryl is typically phenyl, indenyl, azulenyl, naphthyl, biphenyl,as-indacenyl, s-indacenyl, acenaphthylenyl, fluorenyl, phenanthryl,fluoranthenyl, triphenlenyl, chrysenyl, naphthacen, picenyl, perylenyl,pentaphenyl, hexacenyl, pyrenyl, or anthracenyl, preferably phenyl,1-naphthyl, 2-naphthyl, 4-biphenyl, 9-phenanthryl, 2- or 9-fluorenyl, 3-or 4-biphenyl, which may be unsubstituted or substituted. Examples ofC₆-C₁₂aryl are phenyl, 1-naphthyl, 2-naphthyl, 3- or 4-biphenyl, 2- or9-fluorenyl or 9-phenanthryl, which may be unsubstituted or substituted.

C₇-C₂₆aralkyl is typically benzyl, 2-benzyl-2-propyl, β-phenyl-ethyl,α,α-dimethylbenzyl, ω-phenyl-butyl, ω,ω-dimethyl-ω-phenyl-butyl,ω-phenyl-dodecyl, ω-phenyl-octadecyl, ω-phenyl-eicosyl orω-phenyl-docosyl, preferably C₇-C₁₈aralkyl such as benzyl,2-benzyl-2-propyl, β-phenyl-ethyl, α,α-dimethylbenzyl, ω-phenyl-butyl,ω,ω-dimethyl-ωω-phenyl-butyl, ω-phenyl-dodecyl or ω-phenyl-octadecyl,and particularly preferred C₇-C₁₂aralkyl such as benzyl,2-benzyl-2-propyl, β-phenyl-ethyl, α,α-dimethylbenzyl, ω-phenyl-butyl,or ω,ω-dimethyl-ω-phenyl-butyl, in which both the aliphatic hydrocarbongroup and aromatic hydrocarbon group may be unsubstituted orsubstituted. Preferred examples are benzyl, 2-phenylethyl,3-phenylpropyl, naphthylethyl, naphthylmethyl, and cumyl.

The term “carbamoyl group” is typically a C₁₋₁₈carbamoyl radical,preferably C₁₋₈-carbamoyl radical, which may be unsubstituted orsubstituted, such as, for example, carbamoyl, methylcarbamoyl,ethylcarbamoyl, n-butylcarbamoyl, tert-butylcarbamoyl,dimethylcarbamoyloxy, morpholinocarbamoyl or pyrrolidinocarbamoyl.

Heteroaryl is typically C₂-C₂₆heteroaryl (C₂-C₂₀heteroaryl), i.e. a ringwith five to seven ring atoms or a condensed ring system, whereinnitrogen, oxygen or sulfur are the possible hetero atoms, and istypically an unsaturated heterocyclic group with five to 30 atoms havingat least six conjugated π-electrons such as thienyl, benzo[b]thienyl,dibenzo[b,d]thienyl, thianthrenyl, furyl, furfuryl, 2H-pyranyl,benzofuranyl, isobenzofuranyl, dibenzofuranyl, phenoxythienyl, pyrrolyl,imidazolyl, pyrazolyl, pyridyl, bipyridyl, triazinyl, pyrimidinyl,pyrazinyl, pyridazinyl, indolizinyl, isoindolyl, indolyl, indazolyl,purinyl, quinolizinyl, chinolyl, isochinolyl, phthalazinyl,naphthyridinyl, chinoxalinyl, chinazolinyl, cinnolinyl, pteridinyl,carbazolyl, carbolinyl, benzotriazolyl, benzoxazolyl, phenanthridinyl,acridinyl, pyrimidinyl, phenanthrolinyl, phenazinyl, isothiazolyl,phenothiazinyl, isoxazolyl, furazanyl or phenoxazinyl, which can beunsubstituted or substituted.

Possible substituents of the above-mentioned groups are C₁-C₈alkyl, ahydroxyl group, a mercapto group, C₁-C₈alkoxy, C₁-C₈alkylthio, halogen,halo-C₁-C₈alkyl, a cyano group, a carbamoyl group, a nitro group or asilyl group, especially C₁-C₈alkyl, C₁-C₈alkoxy, C₁-C₈alkylthio,halogen, halo-C₁-C₈alkyl, or a cyano group.

As described above, the aforementioned groups may be substituted by Eand/or, if desired, interrupted by D. Interruptions are of coursepossible only in the case of groups containing at least 2 carbon atomsconnected to one another by single bonds; C₆-C₁₈aryl is not interrupted;interrupted arylalkyl or alkylaryl contains the unit D in the alkylmoiety. C₁-C₁₈alkyl substituted by one or more E and/or interrupted byone or more units D is, for example, (CH₂CH₂O)₁₋₉—R^(x), where R^(x) isH or C₁-C₁₀alkyl or C₂-C₁₀alkanoyl (e.g. CO—CH(C₂H₅)C₄H₉),CH₂—CH(OR^(y′))—CH₂—O—R^(y), where R^(y) is C₁-C₁₈alkyl,C₅-C₁₂cycloalkyl, phenyl, C₇-C₁₅-phenylalkyl, and R^(y′) embraces thesame definitions as R^(y) or is H; C₁-C₈alkylene-COO—R^(z), e.g.CH₂COOR^(z), CH(CH₃)COOR^(z), C(CH₃)₂COOR^(z), where R^(z) is H,(CH₂CH₂O)₁₋₉—R^(x), and R^(x) embraces the definitions indicated above;CH₂CH₂—O—CO—CH═CH₂; CH₂CH(OH)CH₂—O—CO—C(CH₃)═CH₂.

The following examples are included for illustrative purposes only anddo not limit the scope of the claims. Unless otherwise stated, all partsand percentages are by weight. Weight-average molecular weight (Mw) andpolydispersity (Mw/Mn=PD) are determined by High Temperature GelPermeation Chromatography (HT-GPC) [Apparatus: GPC PL 220 from Polymerlaboratories (Church Stretton, UK; now Varian) yielding the responsesfrom refractive index (RI), Chromatographic conditions: Column: 3 “PLgelOlexis” column from Polymer Laboratories (Church Stretton, UK); with anaverage particle size of 13 μm (dimensions 300×8 mm I.D.) Mobile phase:1,2,4-trichlorobenzene purified by vacuum distillation and stabilised bybutylhydroxytoluene (BHT, 200 mg/l), Chromatographic temperature: 150°C.; Mobile phase flow: 1 ml/min; Solute concentration: about 1 mg/ml;Injection volume: 200 μl; Detection: RI, Procedure of molecular weightcalibration: Relative calibration is done by use of a set of 10polystyrene calibration standards obtained from Polymer Laboratories(Church Stretton, UK) spanning the molecular weight range from 1,930,000Da-5,050 Da, i.e., PS 1,930,000, PS 1,460,000, PS 1,075,000, PS 560,000,PS 330,000, PS 96,000, PS 52,000, PS 30,300, PS 10,100, PS 5,050 Da. Apolynomic calibration is used to calculate the molecular weight.

All polymer structures given in the examples below are idealizedrepresentations of the polymer products obtained via the polymerizationprocedures described. If more than two components are copolymerized witheach other sequences in the polymers can be either alternating or randomdepending on the polymerisation conditions.

EXAMPLES Example 1 Manufacture of the Semiconducting Compound of theFormula 5

a) 228.06 g of 2-decyl-1-tetradecanol [58670-89-6] are mixed with 484.51g 47% hydroiodic acid [10034-85-2] and the mixture is refluxedovernight. The product is extracted with t-butyl-methylether. Then theorganic phase is dried and concentrated. The product is purified over asilica gel column to give 211.54 g of the desired compound 1 (73%).¹H-NMR data (ppm, CDCl₃): 3.26 2H d, 1.26-1.12 41H m, 0.88 6H t.

b) 5.70 g of the nitril [40985-58-8] are reacted with freshly preparedsodium t-amylate (170 ml t-amylalcohol, 2.22 g sodium and 10 mg FeCl₃)and 5.57 g di-tert-amylsuccinate (DTAS) over night at reflux.Precipitation of the crude DPP from acetic acid affords 5.6 g of thedesired compound 2 (79%). MS m/z: 412.

c) 4 g of compound 2 and 5.6 g potassium carbonate in 200 ml ofdimethylformamide are heated to 90° C. and then 11.82 g of the iodide 1are added and the mixture is then stirred for 3 hours at 90° C. Aftercooling the reaction mixture is poured on water and the product isfiltered and washed with water. Purification is achieved by columnchromatography over silica gel and affords 1.7 g of the desired DPP 3(15%). ¹H-NMR data (ppm, CDCl₃): 9.30 2H s, 7.61 2H d, 7.33 2H d, 4.094H d, 2.01 2H m, 1.35-1.20 80H m, 0.89 6H t, 0.87 6H t.

d) 2.1 g 3 are dissolved in 40 ml of chloroform, cooled down to 0° C.and after the addition of a drop of perchloric acid 0.68 g ofN-bromosuccinimide are then added portion wise over a period of 1 h. Thereaction mixture is stirred at 0° C. After the reaction is completed,the mixture is washed with water. The organic phase is extracted, driedand concentrated. The compound is then purified over a silica gel columnto give 2 g of the desired compound of the formula 4 (84%). ¹H-NMR data(ppm, CDCl₃): 9.21 2H s, 7.33 2H s, 4.05 4H d, 1.97 2H m, 1.35-1.20 80Hm, 0.89 6H t, 0.87 6H t.

e) 810 mg of compound 4, 208 mg thiophene-di-boronic acid pinacol ester[175361-81-6], 15 mg Pd₂(dba)₃ (Tris(dibenzylideneacetone)-di-palladium)and 10 mg tri-tert-butyl-phosphonium-tetrafluoroborate are dissolved in4 ml of tetrahydrofurane. This solution is degassed with 3 cycles offreeze/pump/thaw (Ar). The reaction mixture is then heated to refluxtemperature. Then 418 mg of K₃PO₄ are dissolved in 1.2 ml of water anddegassed under Argon. The water solution is added to the THF solutionand the reaction mixture is refluxed over night. Then 14 mg of2-thiophene-mono-boronic-acid-pinacol-ester [193978-23-3] are added, andthe mixture is refluxed for another 30 minutes. Then 11 mg of2-bromo-thiophene [1003-09-4] are added, and the mixture is refluxed foranother 30 minutes. The reaction mixture is cooled to room temperatureand diluted with water and then extracted with chloroforme. Thechloroforme solution is then refluxed with a solution of NaCN in waterfor 1 hour. The water is separated and the chloroforme solution dried.The residue is then Soxhlet extracted with tetrahydrofurane. The organicphase is precipitated to give 635 mg of the desired polymer 5.Mw=38′000, Polydispersity=2.78 (measured by HT-GPC).

Example 2 Application of the Semiconducting Polymer of the Formula 5

The semiconductor thin film is prepared either by spin-coating thepolymer of the formula 5 obtained in example 1 in a 0.5% (w/w) solutionin chloroform. The spin coating is accomplished at a spinning speed of3000 rpm (rounds per minute) for about 20 seconds in ambient conditions.The devices are evaluated as deposited and after being annealed at 100°C. for 15 minutes.

Transistor Performance

The transistor behavior is measured on an automated transistor prober(TP-10, CSEM Zurich) and showed clear p-type transistor behavior. From alinear fit to the square root of the saturated transfer characteristicsa field effect mobility of 5.6×10⁻³ cm²/Vs with an on/off current ratioof 3.5×10⁵ can be determined.

Example 3 Photovoltaic Application of the Semiconducting Polymer ofFormula 5 DPP-Monomer Based Bulk Heterojunction Solar Cell

The solar cell has the following structure: Al electrode/LiFlayer/organic layer, including compound of theinvention/[poly(3,4-ethylenedioxy-thiophene)(PEDOT)/poly(styrenesulfonic acid) (PSS)]/ITO electrode/glass substrate.The solar cells are made by spin coating a layer of the PEDOT-PSS on apre-patterned ITO on glass substrate. Then a 1:1 mixture of the polymerof formula 5 (1% by weight): [70]PCBM (a substituted C₇₀ fullerene) isspin coated (organic layer). LiF and Al are sublimed under high vacuumthrough a shadow-mask.

Solar Cell Performance

The solar cell is measured under a solar light simulator. Then with theExternal Quantum Efficiency (EQE) graph the current is estimated underAM1.5 conditions. This leads to a value of J_(sc)=2.4 mA/cm², FF=0.51and V_(oc)=0.59 V for an estimated overall efficiency of 0.73%.

Example 4 Synthesis of Polymer 10

a) 228.06 g of 2-decyl-1-tetradecanol [58670-89-6] are mixed with 484.51g 47% hydroiodic acid [10034-85-2] and the mixture is refluxedovernight. The product is extracted with t-butyl-methylether. Then theorganic phase is dried and concentrated. The product is purified over asilica gel column to give 211.54 g of the desired compound 6 (73%).¹H-NMR data (ppm, CDCl₃): 3.26 2H d, 1.26-1.12 41H m, 0.88 6H t.

b) 5.70 g of the nitril [40985-58-8] are reacted with freshly preparedsodium t-amylate (170 ml t-amylalcohol, 2.22 g sodium and 10 mg FeCl₃)and 5.57 g di-tert-amylsuccinate (DTAS) over night at reflux.Precipitation of the crude DPP from acetic acid affords 5.6 g of thedesired compound 7 (79%). MS m/z: 412.

c) 4 g of compound 7 and 5.6 g potassium carbonate in 200 ml ofdimethylformamide are heated to 90° C. and then 11.82 g of the iodide 6are added and the mixture is then stirred for 3 hours at 90° C. Aftercooling the reaction mixture is poured on water and the product isfiltered and washed with water. Purification is achieved by columnchromatography over silica gel and affords 1.7 g of the desired DPP 8(15%). ¹H-NMR data (ppm, CDCl₃): 9.30 2H s, 7.61 2H d, 7.33 2H d, 4.094H d, 2.01 2H m, 1.35-1.20 80H m, 0.89 6H t, 0.87 6H t.

d) 2.1 g 8 are dissolved in 40 ml of chloroform, cooled down to 0° C.and after the addition of a drop of perchloric acid 0.68 g ofN-bromosuccinimide are then added portion wise over a period of 1 h. Thereaction mixture is stirred at 0° C. After the reaction is completed,the mixture is washed with water. The organic phase is extracted, driedand concentrated. The compound is then purified over a silica gel columnto give 2 g of the desired compound of the formula 9 (84%). ¹H-NMR data(ppm, CDCl₃): 9.21 2H s, 7.33 2H s, 4.05 4H d, 1.97 2H m, 1.35-1.20 80Hm, 0.89 6H t, 0.87 6H t.

e) 810 mg of compound 9, 208 mg thiophene-di-boronic acid pinacol ester[175361-81-6], 15 mg Pd₂(dba)₃ (tris(dibenzylideneacetone)-di-palladium)and 10 mg tri-tert-butyl-phosphonium-tetrafluoroborate are dissolved in4 ml of tetrahydrofurane. This solution is degassed with 3 cycles offreeze/pump/thaw (Ar). The reaction mixture is then heated to refluxtemperature. Then 418 mg of K₃PO₄ are dissolved in 1.2 ml of water anddegassed under Argon. The water solution is added to the THF solutionand the reaction mixture is refluxed over night. Then 14 mg of2-thiophene-mono-boronic-acid-pinacol-ester [193978-23-3] are added, andthe mixture is refluxed for another 30 minutes. Then 11 mg of2-bromo-thiophene [1003-09-4] are added, and the mixture is refluxed foranother 30 minutes. The reaction mixture is cooled to room temperatureand diluted with water and then extracted with chloroforme. Thechloroforme solution is then refluxed with a solution of NaCN in waterfor 1 hour. The water is separated and the chloroforme solution dried.The residue is then Soxhlet extracted with tetrahydrofurane. The organicphase is precipitated to give 635 mg of the desired polymer 10.Mw=46,600, Polydispersity=2.72 (measured by HT-GPC).

Example 5 Synthesis of Compound 12

a) A mixture of 5 mg FeCl₃, 1.37 g sodium and 50 ml t-amylalcohol isheated to 110° C. for 30 minutes before a mixture of 3.5 g of nitrile[55219-11-9] and 2.76 g ditertamylsuccinate (DTAS) is added drop wise.The reaction mixture is stirred at 110° C. over night before it ispoured onto a water—methanol mixture. Büchner filtration and exhaustivewashing with methanol affords 3 g of the desired DPP derivative 11 asdark powder. MS m/z: 400.

b) In 10 ml of dry dimethylformamide 1 g of compound 11 is suspended and220 mg of sodiumhydride (60% in mineral oil) are added. The mixture isheated to 100° C. and then 1.86 g of dimethylsulfate is added and themixture is stirred over night at 100° C. The crude product is poured onice, filtered and washed with water. The product is recrystallized fromdimethylformamide to give 0.63 g of a compound of formula 12. MS m/z:428;

Example 6 Application of the Semiconducting Polymer 10

The semiconductor thin film is prepared by spin-coating the polymer 10obtained in example 1 in a 0.5% (w/w) solution in chloroform. The spincoating is accomplished at a spinning speed of 3000 rpm (rounds perminute) for about 20 seconds in ambient conditions. The devices areevaluated as deposited and after being annealed at 100° C. for 15minutes.

Transistor Performance

The transistor behavior is measured on an automated transistor prober(TP-10, CSEM Zurich) and showed clear p-type transistor behavior. From alinear fit to the square root of the saturated transfer characteristicsa field effect mobility of 5.6×10⁻³ cm²/Vs with an on/off current ratioof 3.5×10⁵ can be determined.

Example 7 Photovoltaic Application of the Semiconducting Polymer 10

The solar cell has the following structure: Al electrode/LiFlayer/organic layer, including compound of theinvention/[poly(3,4-ethylenedioxy-thiophene)(PEDOT)/poly(styrenesulfonic acid) (PSS)]/ITO electrode/glass substrate.The solar cells are made by spin coating a layer of the PEDOT-PSS on apre-patterned ITO on glass substrate. Then a 1:1 mixture of the polymer10 (1% by weight): [70]PCBM (a substituted O₇₀ fullerene) is spin coated(organic layer). LiF and Al are sublimed under high vacuum through ashadow-mask.

Solar Cell Performance

The solar cell is measured under a solar light simulator. Then with theExternal Quantum Efficiency (EQE) graph the current is estimated underAM1.5 conditions. This leads to a value of J_(sc)=2.4 mA/cm², FF=0.51and V_(oc)=0.59 V for an estimated overall efficiency of 0.73%.

The invention claimed is:
 1. A compound of formula (III) shown below:

wherein a is 1, 2, or 3, a′ is 0, 1, 2, or 3; b is 0, 1, 2, or 3; b′ is0, 1, 2, or 3; c is 0, 1, 2, or 3; c′ is 0, 1, 2, or 3; d is 0, 1, 2, or3; d′ is 0, 1, 2, or 3; with the proviso that b′ is not 0, if a′ is 0;R¹ and R² may be the same or different and are selected from hydrogen, aC₁-C₁₀₀alkyl group, —COOR¹⁰³, a C₁-C₁₀₀alkyl group which is substitutedby one or more halogen atoms, hydroxyl groups, nitro groups, —CN, orC₆-C₁₈aryl groups or interrupted by —O—, —COO—, —OCO—, or —S—; aC₇-C₁₀₀arylalkyl group, which can be substituted one to three times withC₁-C₈alkyl or C₁-C₈alkoxy; a carbamoyl group, C₅-C₁₂cycloalkyl, whichcan be substituted one to three times with C₁-C₈alkyl or C₁-C₈alkoxy; aC₆-C₂₄aryl group, in particular phenyl or 1- or 2-naphthyl which can besubstituted one to three times with C₁-C₈alkyl, C₁-C₈thioalkoxy, orC₁-C₈alkoxy, or pentafluorophenyl, Ar¹ and Ar^(1′) are independently ofeach other an annulated (aromatic) heterocyclic ring system, containingat least one thiophene ring, which are groups of formula

which may be optionally substituted by one, or more groups, R³ andR^(3′) are independently of each other hydrogen, halogen, C₁-C₂₅alkyl,which may optionally be interrupted by one or more oxygen or sulphuratoms; C₇-C₂₅arylalkyl, or C₁-C₂₅alkoxy; R⁴, R^(4′), R⁵, R^(5′), R⁶ andR^(6′) are independently of each other hydrogen, halogen, C₁-C₂₅alkyl,which may optionally be interrupted by one or more oxygen or sulphuratoms; C₇-C₂₅arylalkyl, or C₁-C₂₅alkoxy; R¹¹⁴ is C₁-C₂₅alkyl, which mayoptionally be interrupted by one, or more oxygen, or sulphur atoms, R⁷,R^(7′), R⁹ and R^(9′) are independently of each other hydrogen,C₁-C₂₅alkyl, which may optionally be interrupted by one, or more oxygen,or sulphur atoms; or C₇-C₂₅arylalkyl, R⁸ and R^(8′) are independently ofeach other hydrogen, C₆-C₁₈aryl; C₆-C₁₈aryl which is substituted byC₁-C₁₈alkyl, or C₁-C₁₈alkoxy; or C₁-C₂₅alkyl, which may optionally beinterrupted by one or more oxygen or sulphur atoms; or C₇-C₂₅arylalkyl,R¹¹ and R^(11′) are independently of each other C₁-C₂₅alkyl group,C₇-C₂₅arylalkyl, or a phenyl group, which can be substituted one tothree times with C₁-C₈alkyl or C₁-C₈alkoxy; R¹² and R^(12′) areindependently of each other hydrogen, halogen, C₁-C₂₅alkyl, which mayoptionally be interrupted by one, or more oxygen, or sulphur atoms,C₁-C₂₅alkoxy, C₇-C₂₅arylalkyl, or

R¹³, wherein R¹³ is a C₁-C₁₀alkyl group, or a tri(C₁-C₈alkyl)silylgroup, Ar², Ar²′, Ar³, Ar³′, Ar⁴ and Ar⁴′ have the meaning of Ar¹, orare independently of each other

wherein one of X³ and X⁴ is N and the other is CR⁹⁹, R⁹⁹, R¹⁰⁴ andR^(104′) are independently of each other hydrogen, halogen, or aC₁-C₂₅alkyl group, which may optionally be interrupted by one or moreoxygen or sulphur atoms, C₇-C₂₅arylalkyl, or a C₁-C₂₅alkoxy group, R¹⁰⁵,R^(105′), R¹⁰⁶ and R^(106′) are independently of each other hydrogen,halogen, C₁-C₂₅alkyl, which may optionally be interrupted by one or moreoxygen or sulphur atoms; C₇-C₂₅arylalkyl, or C₁-C₁₈alkoxy, R¹⁰⁷ isC₇-C₂₅arylalkyl, C₆-C₁₈aryl; C₆-C₁₈aryl which is substituted byC₁-C₁₈alkyl, C₁-C₁₈perfluoroalkyl, or C₁-C₁₈alkoxy; C₁-C₁₈alkyl;C₁-C₁₈alkyl which is interrupted by —O—, or —S—; or —COOR¹⁰³; R¹⁰³ isC₁-C₅₀alkyl; R¹⁰⁸ and R¹⁰⁹ are independently of each other H,C₁-C₂₅alkyl, C₁-C₂₅alkyl which is substituted by E or interrupted by D,C₇-C₂₅arylalkyl, C₆-C₂₄aryl, C₆-C₂₄aryl which is substituted by G,C₂-C₂₀heteroaryl, C₂-C₂₀heteroaryl which is substituted by G,C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₁-C₁₈alkoxy, C₁-C₁₈alkoxy which issubstituted by E or interrupted by D, or C₇-C₂₅aralkyl, or R¹⁰⁸ and R¹⁰⁹together form a group of formula ═cR¹¹⁰R¹¹¹, wherein R¹¹⁰ and R¹¹¹ areindependently of each other H, C₁-C₁₈alkyl, C₁-C₁₈alkyl which issubstituted by E or interrupted by D, C₆-C₂₄aryl, C₆-C₂₄aryl which issubstituted by G, or C₂-C₂₀heteroaryl, or C₂-C₂₀heteroaryl which issubstituted by G, or R¹⁰⁸ and R¹⁰⁹ together form a five or six memberedring, which optionally can be substituted by C₁-C₁₈alkyl, C₁-C₁₈alkylwhich is substituted by E or interrupted by D, C₆-C₂₄aryl, C₆-C₂₄arylwhich is substituted by G, C₂-C₂₀heteroaryl, C₂-C₂₀heteroaryl which issubstituted by G, C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₁-C₁₈alkoxy,C₁-C₁₈alkoxy which is substituted by E or interrupted by D, orC₇-C₂₅aralkyl, R¹⁰ and R^(10′) are independently of each other hydrogen,halogen, C₁-C₂₅alkyl, C₁-C₂₅alkoxy, or a group of one of the formulaeIVa to IVi,

wherein R²² to R²⁶ and R²⁹ to R⁵⁸ represent independently of each otherH, halogen, C₁-C₂₅alkyl, C₁-C₂₅alkyl which is substituted by E orinterrupted by D, C₆-C₂₄aryl, C₆-C₂₄aryl which is substituted by G,C₂-C₂₀heteroaryl, C₂-C₂₀heteroaryl which is substituted by G, aC₄-C₁₈cycloalkyl group, a C₄-C₁₈cycloalkyl group, which is substitutedby G, C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₁-C₁₈alkoxy, C₁-C₁₈alkoxy which issubstituted by E or interrupted by D, C₇-C₂₅aralkyl, or C₇-C₂₅aralkyl,which is substituted by G, R²⁷ and R²⁸ are independently of each otherhydrogen, C₁-C₂₅alkyl, or C₇-C₂₅aralkyl, or R²⁷ and R²⁸ togetherrepresent alkylene or alkenylene which may be both bonded via oxygen orsulfur to the thienyl residue and which may both have up to 25 carbonatoms, D is —CO—, —COO—, —S—, —O—, or —NR¹¹²—, E is C₁-C₈thioalkoxy,C₁-C₈alkoxy, CN, —NR¹¹²R¹¹³, —CONR¹¹²R¹¹³, or halogen, G is E, orC₁-C₁₈alkyl, and R¹¹² and R¹¹³ are independently of each other H;C₆-C₁₈aryl; C₆-C₁₈aryl which is substituted by C₁-C₁₈alkyl, orC₁-C₁₈alkoxy; C₁-C₁₈alkyl; or C₁-C₁₈alkyl which is interrupted by —O—;with the proviso that the following compound

is excluded.
 2. An organic semiconductor material, layer or component,comprising a compound according to claim
 1. 3. A semiconductor devicecomprising a compound according to claim
 1. 4. The semiconductor deviceaccording to claim 3 is an organic photovoltaic device including a solarcell, a photodiode, or an organic field effect transistor.
 5. A processfor the preparation of an organic semiconductor device, which processcomprises applying a solution or dispersion of a compound according toclaim 1 in an organic solvent to a suitable substrate and removing thesolvent.
 6. The compound according to claim 1, wherein a and a′ are 1,b, b′, c, c′, d, and d′ are 0, Ar¹ and Ar^(1′) are the same and aregroups of formula (Xa), (Xc), or (Xg), and R¹ and R² are the same andare a C₁-C₁₀₀alkyl group.